diff --git a/test/language/expressions/class/fields-duplicate-privatenames.js b/test/language/expressions/class/fields-duplicate-privatenames.js
new file mode 100644
index 0000000000000000000000000000000000000000..8d1d03da1488632b28781847aa0c13795e0eda87
--- /dev/null
+++ b/test/language/expressions/class/fields-duplicate-privatenames.js
@@ -0,0 +1,24 @@
+// Copyright 2017 Valerie Young.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Syntax error if the same private field defined twice
+esid: sec-class-definitions-static-semantics-early-errors
+features: [class-fields]
+negative:
+  phase: early
+  type: SyntaxError
+info: |
+  Static Semantics: Early Errors
+
+    ClassBody : ClassElementList
+    It is a Syntax Error if PrivateBoundNames of ClassBody contains any duplicate entries.
+---*/
+
+
+throw "Test262: This statement should not be evaluated.";
+
+var C = class {
+  #x;
+  #x;
+}
diff --git a/test/language/statements/class/fields-duplicate-privatenames.js b/test/language/statements/class/fields-duplicate-privatenames.js
new file mode 100644
index 0000000000000000000000000000000000000000..ee77d36ae23dfa7c7049e6ff59cb078fb7f82a30
--- /dev/null
+++ b/test/language/statements/class/fields-duplicate-privatenames.js
@@ -0,0 +1,24 @@
+// Copyright 2017 Valerie Young.  All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: Syntax error if the same private field defined twice
+esid: sec-class-definitions-static-semantics-early-errors
+features: [class-fields]
+negative:
+  phase: early
+  type: SyntaxError
+info: |
+  Static Semantics: Early Errors
+
+    ClassBody : ClassElementList
+    It is a Syntax Error if PrivateBoundNames of ClassBody contains any duplicate entries.
+---*/
+
+
+throw "Test262: This statement should not be evaluated.";
+
+class C {
+  #x;
+  #x;
+}