diff --git a/test/unittest/CMakeLists.txt b/test/unittest/CMakeLists.txt
index 52d5acd..bcc16d9 100644
--- a/test/unittest/CMakeLists.txt
+++ b/test/unittest/CMakeLists.txt
@@ -10,6 +10,7 @@ set(UNITTEST_SOURCES
     namespacetest.cpp
     prettywritertest.cpp
     readertest.cpp
+	simdtest.cpp
     stringbuffertest.cpp
     strtodtest.cpp
     unittest.cpp
@@ -36,8 +37,9 @@ add_test(NAME unittest
     WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}/bin)
 
 if(NOT MSVC)
+    # Not running SIMD.* unit test cases for Valgrind
     add_test(NAME valgrind_unittest
-        COMMAND valgrind --leak-check=full --error-exitcode=1 ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/unittest
+        COMMAND valgrind --leak-check=full --error-exitcode=1 ${CMAKE_RUNTIME_OUTPUT_DIRECTORY}/unittest --gtest_filter=-SIMD.*
         WORKING_DIRECTORY ${CMAKE_SOURCE_DIR}/bin)
 
     if(CMAKE_BUILD_TYPE STREQUAL "Debug")
diff --git a/test/unittest/simdtest.cpp b/test/unittest/simdtest.cpp
new file mode 100644
index 0000000..42fb10f
--- /dev/null
+++ b/test/unittest/simdtest.cpp
@@ -0,0 +1,59 @@
+// Copyright (C) 2011 Milo Yip
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+// Since Travis CI installs old Valgrind 3.7.0, which fails with some SSE4.2
+// The unit tests prefix with SIMD should be skipped by Valgrind test
+
+// __SSE2__ and __SSE4_2__ are recognized by gcc, clang, and the Intel compiler.
+// We use -march=native with gmake to enable -msse2 and -msse4.2, if supported.
+#if defined(__SSE4_2__)
+#  define RAPIDJSON_SSE42
+#elif defined(__SSE2__)
+#  define RAPIDJSON_SSE2
+#endif
+
+#include "unittest.h"
+
+#include "rapidjson/reader.h"
+
+using namespace rapidjson;
+
+#ifdef RAPIDJSON_SSE2
+#define SIMD_SUFFIX(name) name##_SSE2
+#elif defined(RAPIDJSON_SSE42)
+#define SIMD_SUFFIX(name) name##_SSE42
+#else
+#define SIMD_SUFFIX(name) name
+#endif
+
+TEST(SIMD, SIMD_SUFFIX(SkipWhitespace)) {
+    char buffer[258];
+    for (size_t i = 0; i < 256; i++)
+        buffer[i] = " \t\r\n"[i % 4];
+    buffer[256] = 'X';
+    buffer[257] = '\0';
+
+    // Try to start from different position, to test different memory alignments
+    for (size_t i = 0; i < 256; i++) {
+        StringStream s(buffer + i);
+        SkipWhitespace(s);
+        EXPECT_EQ('X', s.Peek());
+    }
+}