diff --git a/jerry-core/parser/js/lexer.cpp b/jerry-core/parser/js/lexer.cpp
index 01cda92d3..db6dc8940 100644
--- a/jerry-core/parser/js/lexer.cpp
+++ b/jerry-core/parser/js/lexer.cpp
@@ -969,6 +969,13 @@ lexer_parse_number (void)
             consume_char ();
           }
 
+          if (!lit_char_is_decimal_digit (LA (0)))
+          {
+            PARSE_ERROR (JSP_EARLY_ERROR_SYNTAX,
+                         "Exponential mark in a numeric literal should followed by a singed interger",
+                         lit_utf8_iterator_get_pos (&src_iter));
+          }
+
           continue;
         }
       }
diff --git a/tests/jerry/regression-test-issue-339.js b/tests/jerry/regression-test-issue-339.js
new file mode 100644
index 000000000..08bcd6d2d
--- /dev/null
+++ b/tests/jerry/regression-test-issue-339.js
@@ -0,0 +1,24 @@
+// Copyright 2015 Samsung Electronics Co., Ltd.
+// Copyright 2015 University of Szeged.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+try
+{
+  eval ('var y = 4e;');
+  assert (false);
+}
+catch (e)
+{
+  assert (e instanceof SyntaxError);
+}