diff --git a/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/rules/HiveExpandDistinctAggregatesRule.java b/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/rules/HiveExpandDistinctAggregatesRule.java
index 3a46498298b6..6dc4ccbd48cf 100644
--- a/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/rules/HiveExpandDistinctAggregatesRule.java
+++ b/ql/src/java/org/apache/hadoop/hive/ql/optimizer/calcite/rules/HiveExpandDistinctAggregatesRule.java
@@ -161,7 +161,14 @@ public void onMatch(RelOptRuleCall call) {
     // arguments then we can use a more efficient form.
     final RelMetadataQuery mq = call.getMetadataQuery();
     if ((nonDistinctCount == 0) && (argListSets.size() == 1)) {
-      for (Integer arg : argListSets.iterator().next()) {
+      List<Integer> argList = argListSets.iterator().next();
+      // When COUNT(DISTINCT a, b, ...) has multiple columns convertMonopole -> rewriteAggCalls 
+      // would produce COUNT(a, b) without DISTINCT at the top level, which is semantically 
+      // wrong and is rejected by GenericUDAFCount.
+      if (argList.size() > 1 && numCountDistinct > 0) {
+        return;
+      }
+      for (Integer arg : argList) {
         Set<RelColumnOrigin> colOrigs = mq.getColumnOrigins(aggregate.getInput(), arg);
         if (null != colOrigs) {
           for (RelColumnOrigin colOrig : colOrigs) {
@@ -173,12 +180,8 @@ public void onMatch(RelOptRuleCall call) {
           }
         }
       }
-      RelNode converted =
-          convertMonopole(
-              aggregate,
-              argListSets.iterator().next());
+      RelNode converted = convertMonopole(aggregate, argList);
       call.transformTo(converted);
-      return;
     }
   }
 
diff --git a/ql/src/test/queries/clientpositive/count_distinct_multi_col.q b/ql/src/test/queries/clientpositive/count_distinct_multi_col.q
new file mode 100644
index 000000000000..4cb19313a79c
--- /dev/null
+++ b/ql/src/test/queries/clientpositive/count_distinct_multi_col.q
@@ -0,0 +1,80 @@
+create table t (col1 string, col2 int, col3 int, col4 date);
+
+insert into t values
+  ('a', 1,  2,  '2022-01-01'),
+  ('a', 1,  2,  '2022-01-01'),
+  ('a', 1,  2,  '2022-01-02'),
+  ('a', 1,  22, '2022-01-02'),
+  ('a', 11, 2,  '2022-01-01'),
+  ('a', 11, 2,  '2022-01-02');
+
+-- single-column: HiveExpandDistinctAggregatesRule matched -> two HiveAggregate operators in plan
+explain cbo
+SELECT col1, col2, COUNT(DISTINCT col3) AS cnt
+FROM t
+GROUP BY col1, col2;
+
+SELECT col1, col2, COUNT(DISTINCT col3) AS cnt
+FROM t
+GROUP BY col1, col2
+ORDER BY col1, col2;
+
+-- multi-column: HiveExpandDistinctAggregatesRule !matched -> single HiveAggregate operator
+explain cbo
+SELECT col1, col2, COUNT(DISTINCT col3, col4) AS cnt
+FROM t
+GROUP BY col1, col2;
+
+SELECT col1, col2, COUNT(DISTINCT col3, col4) AS cnt
+FROM t
+GROUP BY col1, col2
+ORDER BY col1, col2;
+
+-- 3-column: HiveExpandDistinctAggregatesRule !matched -> single HiveAggregate operator
+explain cbo
+SELECT col1, COUNT(DISTINCT col2, col3, col4) AS cnt
+FROM t
+GROUP BY col1;
+
+SELECT col1, COUNT(DISTINCT col2, col3, col4) AS cnt
+FROM t
+GROUP BY col1;
+
+-- multi-column distinct alongside a non-distinct aggregate: single HiveAggregate operator
+explain cbo
+SELECT col1, col2, COUNT(DISTINCT col3, col4) AS cnt, SUM(col3) AS s
+FROM t
+GROUP BY col1, col2;
+
+SELECT col1, col2, COUNT(DISTINCT col3, col4) AS cnt, SUM(col3) AS s
+FROM t
+GROUP BY col1, col2
+ORDER BY col1, col2;
+
+-- multiple COUNT DISTINCT with different single-column arg: uses grouping-sets
+explain cbo
+SELECT col1, COUNT(DISTINCT col3) AS c3, COUNT(DISTINCT col2) AS c2
+FROM t
+GROUP BY col1;
+
+SELECT col1, COUNT(DISTINCT col3) AS c3, COUNT(DISTINCT col2) AS c2
+FROM t
+GROUP BY col1;
+
+-- 2 COUNT DISTINCTs each with multiple columns: uses grouping-sets path
+explain cbo
+SELECT col1, COUNT(DISTINCT col2, col3) AS c1, COUNT(DISTINCT col3, col4) AS c2
+FROM t
+GROUP BY col1;
+
+SELECT col1, COUNT(DISTINCT col2, col3) AS c1, COUNT(DISTINCT col3, col4) AS c2
+FROM t
+GROUP BY col1;
+
+-- CTAS
+create table t_ctas as
+SELECT col1, col2, COUNT(DISTINCT col3, col4) AS cnt
+FROM t
+GROUP BY col1, col2;
+
+select * from t_ctas ORDER BY col1, col2;
diff --git a/ql/src/test/results/clientpositive/llap/count_distinct_multi_col.q.out b/ql/src/test/results/clientpositive/llap/count_distinct_multi_col.q.out
new file mode 100644
index 000000000000..0bcef57e2304
--- /dev/null
+++ b/ql/src/test/results/clientpositive/llap/count_distinct_multi_col.q.out
@@ -0,0 +1,270 @@
+PREHOOK: query: create table t (col1 string, col2 int, col3 int, col4 date)
+PREHOOK: type: CREATETABLE
+PREHOOK: Output: database:default
+PREHOOK: Output: default@t
+POSTHOOK: query: create table t (col1 string, col2 int, col3 int, col4 date)
+POSTHOOK: type: CREATETABLE
+POSTHOOK: Output: database:default
+POSTHOOK: Output: default@t
+PREHOOK: query: insert into t values
+  ('a', 1,  2,  '2022-01-01'),
+  ('a', 1,  2,  '2022-01-01'),
+  ('a', 1,  2,  '2022-01-02'),
+  ('a', 1,  22, '2022-01-02'),
+  ('a', 11, 2,  '2022-01-01'),
+  ('a', 11, 2,  '2022-01-02')
+PREHOOK: type: QUERY
+PREHOOK: Input: _dummy_database@_dummy_table
+PREHOOK: Output: default@t
+POSTHOOK: query: insert into t values
+  ('a', 1,  2,  '2022-01-01'),
+  ('a', 1,  2,  '2022-01-01'),
+  ('a', 1,  2,  '2022-01-02'),
+  ('a', 1,  22, '2022-01-02'),
+  ('a', 11, 2,  '2022-01-01'),
+  ('a', 11, 2,  '2022-01-02')
+POSTHOOK: type: QUERY
+POSTHOOK: Input: _dummy_database@_dummy_table
+POSTHOOK: Output: default@t
+POSTHOOK: Lineage: t.col1 SCRIPT []
+POSTHOOK: Lineage: t.col2 SCRIPT []
+POSTHOOK: Lineage: t.col3 SCRIPT []
+POSTHOOK: Lineage: t.col4 SCRIPT []
+PREHOOK: query: explain cbo
+SELECT col1, col2, COUNT(DISTINCT col3) AS cnt
+FROM t
+GROUP BY col1, col2
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t
+#### A masked pattern was here ####
+POSTHOOK: query: explain cbo
+SELECT col1, col2, COUNT(DISTINCT col3) AS cnt
+FROM t
+GROUP BY col1, col2
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t
+#### A masked pattern was here ####
+CBO PLAN:
+HiveProject(col1=[$0], col2=[$1], cnt=[$2])
+  HiveAggregate(group=[{0, 1}], agg#0=[count($2)])
+    HiveProject(col1=[$0], col2=[$1], col3=[$2])
+      HiveAggregate(group=[{0, 1, 2}])
+        HiveTableScan(table=[[default, t]], table:alias=[t])
+
+PREHOOK: query: SELECT col1, col2, COUNT(DISTINCT col3) AS cnt
+FROM t
+GROUP BY col1, col2
+ORDER BY col1, col2
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t
+#### A masked pattern was here ####
+POSTHOOK: query: SELECT col1, col2, COUNT(DISTINCT col3) AS cnt
+FROM t
+GROUP BY col1, col2
+ORDER BY col1, col2
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t
+#### A masked pattern was here ####
+a	1	2
+a	11	1
+PREHOOK: query: explain cbo
+SELECT col1, col2, COUNT(DISTINCT col3, col4) AS cnt
+FROM t
+GROUP BY col1, col2
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t
+#### A masked pattern was here ####
+POSTHOOK: query: explain cbo
+SELECT col1, col2, COUNT(DISTINCT col3, col4) AS cnt
+FROM t
+GROUP BY col1, col2
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t
+#### A masked pattern was here ####
+CBO PLAN:
+HiveProject(col1=[$0], col2=[$1], cnt=[$2])
+  HiveAggregate(group=[{0, 1}], agg#0=[count(DISTINCT $2, $3)])
+    HiveTableScan(table=[[default, t]], table:alias=[t])
+
+PREHOOK: query: SELECT col1, col2, COUNT(DISTINCT col3, col4) AS cnt
+FROM t
+GROUP BY col1, col2
+ORDER BY col1, col2
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t
+#### A masked pattern was here ####
+POSTHOOK: query: SELECT col1, col2, COUNT(DISTINCT col3, col4) AS cnt
+FROM t
+GROUP BY col1, col2
+ORDER BY col1, col2
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t
+#### A masked pattern was here ####
+a	1	3
+a	11	2
+PREHOOK: query: explain cbo
+SELECT col1, COUNT(DISTINCT col2, col3, col4) AS cnt
+FROM t
+GROUP BY col1
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t
+#### A masked pattern was here ####
+POSTHOOK: query: explain cbo
+SELECT col1, COUNT(DISTINCT col2, col3, col4) AS cnt
+FROM t
+GROUP BY col1
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t
+#### A masked pattern was here ####
+CBO PLAN:
+HiveProject(col1=[$0], cnt=[$1])
+  HiveAggregate(group=[{0}], agg#0=[count(DISTINCT $1, $2, $3)])
+    HiveTableScan(table=[[default, t]], table:alias=[t])
+
+PREHOOK: query: SELECT col1, COUNT(DISTINCT col2, col3, col4) AS cnt
+FROM t
+GROUP BY col1
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t
+#### A masked pattern was here ####
+POSTHOOK: query: SELECT col1, COUNT(DISTINCT col2, col3, col4) AS cnt
+FROM t
+GROUP BY col1
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t
+#### A masked pattern was here ####
+a	5
+PREHOOK: query: explain cbo
+SELECT col1, col2, COUNT(DISTINCT col3, col4) AS cnt, SUM(col3) AS s
+FROM t
+GROUP BY col1, col2
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t
+#### A masked pattern was here ####
+POSTHOOK: query: explain cbo
+SELECT col1, col2, COUNT(DISTINCT col3, col4) AS cnt, SUM(col3) AS s
+FROM t
+GROUP BY col1, col2
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t
+#### A masked pattern was here ####
+CBO PLAN:
+HiveProject(col1=[$0], col2=[$1], cnt=[$2], s=[$3])
+  HiveAggregate(group=[{0, 1}], agg#0=[count(DISTINCT $2, $3)], agg#1=[sum($2)])
+    HiveTableScan(table=[[default, t]], table:alias=[t])
+
+PREHOOK: query: SELECT col1, col2, COUNT(DISTINCT col3, col4) AS cnt, SUM(col3) AS s
+FROM t
+GROUP BY col1, col2
+ORDER BY col1, col2
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t
+#### A masked pattern was here ####
+POSTHOOK: query: SELECT col1, col2, COUNT(DISTINCT col3, col4) AS cnt, SUM(col3) AS s
+FROM t
+GROUP BY col1, col2
+ORDER BY col1, col2
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t
+#### A masked pattern was here ####
+a	1	3	28
+a	11	2	4
+PREHOOK: query: explain cbo
+SELECT col1, COUNT(DISTINCT col3) AS c3, COUNT(DISTINCT col2) AS c2
+FROM t
+GROUP BY col1
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t
+#### A masked pattern was here ####
+POSTHOOK: query: explain cbo
+SELECT col1, COUNT(DISTINCT col3) AS c3, COUNT(DISTINCT col2) AS c2
+FROM t
+GROUP BY col1
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t
+#### A masked pattern was here ####
+CBO PLAN:
+HiveProject(col1=[$0], c3=[$1], c2=[$2])
+  HiveAggregate(group=[{2}], agg#0=[count($0)], agg#1=[count($1)])
+    HiveProject($f0=[CASE(AND(=($3, 1), IS NOT NULL($1)), 1, null:INTEGER)], $f1=[CASE(AND(=($3, 2), IS NOT NULL($2)), 1, null:INTEGER)], $f2=[$0])
+      HiveAggregate(group=[{0, 1, 2}], groups=[[{0, 1}, {0, 2}]], GROUPING__ID=[GROUPING__ID()])
+        HiveProject($f0=[$0], $f1=[$2], $f2=[$1])
+          HiveTableScan(table=[[default, t]], table:alias=[t])
+
+PREHOOK: query: SELECT col1, COUNT(DISTINCT col3) AS c3, COUNT(DISTINCT col2) AS c2
+FROM t
+GROUP BY col1
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t
+#### A masked pattern was here ####
+POSTHOOK: query: SELECT col1, COUNT(DISTINCT col3) AS c3, COUNT(DISTINCT col2) AS c2
+FROM t
+GROUP BY col1
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t
+#### A masked pattern was here ####
+a	2	2
+PREHOOK: query: explain cbo
+SELECT col1, COUNT(DISTINCT col2, col3) AS c1, COUNT(DISTINCT col3, col4) AS c2
+FROM t
+GROUP BY col1
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t
+#### A masked pattern was here ####
+POSTHOOK: query: explain cbo
+SELECT col1, COUNT(DISTINCT col2, col3) AS c1, COUNT(DISTINCT col3, col4) AS c2
+FROM t
+GROUP BY col1
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t
+#### A masked pattern was here ####
+CBO PLAN:
+HiveProject(col1=[$0], c1=[$1], c2=[$2])
+  HiveAggregate(group=[{2}], agg#0=[count($0)], agg#1=[count($1)])
+    HiveProject($f0=[CASE(=($4, 1), 1, null:INTEGER)], $f1=[CASE(=($4, 4), 1, null:INTEGER)], $f2=[$0])
+      HiveAggregate(group=[{0, 1, 2, 3}], groups=[[{0, 1, 2}, {0, 2, 3}]], GROUPING__ID=[GROUPING__ID()])
+        HiveProject($f0=[$0], $f1=[$1], $f2=[$2], $f3=[$3])
+          HiveTableScan(table=[[default, t]], table:alias=[t])
+
+PREHOOK: query: SELECT col1, COUNT(DISTINCT col2, col3) AS c1, COUNT(DISTINCT col3, col4) AS c2
+FROM t
+GROUP BY col1
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t
+#### A masked pattern was here ####
+POSTHOOK: query: SELECT col1, COUNT(DISTINCT col2, col3) AS c1, COUNT(DISTINCT col3, col4) AS c2
+FROM t
+GROUP BY col1
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t
+#### A masked pattern was here ####
+a	3	3
+PREHOOK: query: create table t_ctas as
+SELECT col1, col2, COUNT(DISTINCT col3, col4) AS cnt
+FROM t
+GROUP BY col1, col2
+PREHOOK: type: CREATETABLE_AS_SELECT
+PREHOOK: Input: default@t
+PREHOOK: Output: database:default
+PREHOOK: Output: default@t_ctas
+POSTHOOK: query: create table t_ctas as
+SELECT col1, col2, COUNT(DISTINCT col3, col4) AS cnt
+FROM t
+GROUP BY col1, col2
+POSTHOOK: type: CREATETABLE_AS_SELECT
+POSTHOOK: Input: default@t
+POSTHOOK: Output: database:default
+POSTHOOK: Output: default@t_ctas
+POSTHOOK: Lineage: t_ctas.cnt EXPRESSION [(t)t.FieldSchema(name:col3, type:int, comment:null), (t)t.FieldSchema(name:col4, type:date, comment:null), ]
+POSTHOOK: Lineage: t_ctas.col1 SIMPLE [(t)t.FieldSchema(name:col1, type:string, comment:null), ]
+POSTHOOK: Lineage: t_ctas.col2 SIMPLE [(t)t.FieldSchema(name:col2, type:int, comment:null), ]
+PREHOOK: query: select * from t_ctas ORDER BY col1, col2
+PREHOOK: type: QUERY
+PREHOOK: Input: default@t_ctas
+#### A masked pattern was here ####
+POSTHOOK: query: select * from t_ctas ORDER BY col1, col2
+POSTHOOK: type: QUERY
+POSTHOOK: Input: default@t_ctas
+#### A masked pattern was here ####
+a	1	3
+a	11	2