diff --git a/lib/create-config-gypi.js b/lib/create-config-gypi.js
index d471da5169..5bf6ca945e 100644
--- a/lib/create-config-gypi.js
+++ b/lib/create-config-gypi.js
@@ -10,8 +10,13 @@ function parseConfigGypi (config) {
   config = config.replace(/#.*/g, '')
   // 2. join multiline strings
   config = config.replace(/'$\s+'/mg, '')
-  // 3. normalize string literals from ' into "
-  config = config.replace(/'/g, '"')
+  // 3. normalize string literals from ' into ", escaping any double-quote
+  // characters that appear inside a single-quoted string (e.g. GYP condition
+  // strings such as 'OS=="win"') so the result is still valid JSON
+  config = config.replace(/'(?:[^'\\]|\\.)*'/g, (str) => {
+    const inner = str.slice(1, -1).replace(/\\'/g, "'").replace(/"/g, '\\"')
+    return `"${inner}"`
+  })
   return JSON.parse(config)
 }
 
diff --git a/test/test-create-config-gypi.js b/test/test-create-config-gypi.js
index 602fd3d678..30cd291b67 100644
--- a/test/test-create-config-gypi.js
+++ b/test/test-create-config-gypi.js
@@ -76,4 +76,10 @@ describe('create-config-gypi', function () {
     const config = parseConfigGypi(str)
     assert.deepStrictEqual(config, { variables: { multiline: 'AB' } })
   })
+
+  it('config.gypi parsing with double quotes inside single-quoted strings', function () {
+    const str = '{\'variables\': {\'cond\': \'OS=="win"\', \'flags\': \'-DFOO="x"\'}}'
+    const config = parseConfigGypi(str)
+    assert.deepStrictEqual(config, { variables: { cond: 'OS=="win"', flags: '-DFOO="x"' } })
+  })
 })