diff --git a/net/base/net_log_logger_unittest.cc b/net/base/net_log_logger_unittest.cc
new file mode 100644
index 0000000..2f63b8d
--- /dev/null
+++ b/net/base/net_log_logger_unittest.cc
@@ -0,0 +1,140 @@
+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "net/base/net_log_logger.h"
+
+#include "base/files/file_path.h"
+#include "base/files/file_util.h"
+#include "base/files/scoped_temp_dir.h"
+#include "base/json/json_reader.h"
+#include "base/values.h"
+#include "net/base/net_log.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace net {
+
+namespace {
+
+class NetLogLoggerTest : public testing::Test {
+ public:
+  virtual void SetUp() {
+    ASSERT_TRUE(temp_dir_.CreateUniqueTempDir());
+    log_path_ = temp_dir_.path().AppendASCII("NetLogFile");
+  }
+
+ protected:
+  base::ScopedTempDir temp_dir_;
+  base::FilePath log_path_;
+};
+
+TEST_F(NetLogLoggerTest, GeneratesValidJSONForNoEvents) {
+  // Create and destroy a logger.
+  FILE* file = base::OpenFile(log_path_, "w");
+  ASSERT_TRUE(file);
+  scoped_ptr<base::Value> constants(NetLogLogger::GetConstants());
+  scoped_ptr<NetLogLogger> logger(new NetLogLogger(file, *constants));
+  logger.reset();
+
+  std::string input;
+  ASSERT_TRUE(base::ReadFileToString(log_path_, &input));
+
+  base::JSONReader reader;
+  scoped_ptr<base::Value> root(reader.ReadToValue(input));
+  ASSERT_TRUE(root) << reader.GetErrorMessage();
+
+  base::DictionaryValue* dict;
+  ASSERT_TRUE(root->GetAsDictionary(&dict));
+  base::ListValue* events;
+  ASSERT_TRUE(dict->GetList("events", &events));
+  ASSERT_EQ(0u, events->GetSize());
+}
+
+// Make sure the log level is LOG_STRIP_PRIVATE_DATA by default.
+TEST_F(NetLogLoggerTest, LogLevel) {
+  FILE* file = base::OpenFile(log_path_, "w");
+  ASSERT_TRUE(file);
+  scoped_ptr<base::Value> constants(NetLogLogger::GetConstants());
+  NetLogLogger logger(file, *constants);
+
+  NetLog net_log;
+  logger.StartObserving(&net_log);
+  EXPECT_EQ(NetLog::LOG_STRIP_PRIVATE_DATA, logger.log_level());
+  EXPECT_EQ(NetLog::LOG_STRIP_PRIVATE_DATA, net_log.GetLogLevel());
+  logger.StopObserving();
+
+  logger.set_log_level(NetLog::LOG_ALL_BUT_BYTES);
+  logger.StartObserving(&net_log);
+  EXPECT_EQ(NetLog::LOG_ALL_BUT_BYTES, logger.log_level());
+  EXPECT_EQ(NetLog::LOG_ALL_BUT_BYTES, net_log.GetLogLevel());
+  logger.StopObserving();
+}
+
+TEST_F(NetLogLoggerTest, GeneratesValidJSONWithOneEvent) {
+  FILE* file = base::OpenFile(log_path_, "w");
+  ASSERT_TRUE(file);
+  scoped_ptr<base::Value> constants(NetLogLogger::GetConstants());
+  scoped_ptr<NetLogLogger> logger(new NetLogLogger(file, *constants));
+
+  const int kDummyId = 1;
+  NetLog::Source source(NetLog::SOURCE_SPDY_SESSION, kDummyId);
+  NetLog::EntryData entry_data(NetLog::TYPE_PROXY_SERVICE,
+                               source,
+                               NetLog::PHASE_BEGIN,
+                               base::TimeTicks::Now(),
+                               NULL);
+  NetLog::Entry entry(&entry_data, NetLog::LOG_ALL);
+  logger->OnAddEntry(entry);
+  logger.reset();
+
+  std::string input;
+  ASSERT_TRUE(base::ReadFileToString(log_path_, &input));
+
+  base::JSONReader reader;
+  scoped_ptr<base::Value> root(reader.ReadToValue(input));
+  ASSERT_TRUE(root) << reader.GetErrorMessage();
+
+  base::DictionaryValue* dict;
+  ASSERT_TRUE(root->GetAsDictionary(&dict));
+  base::ListValue* events;
+  ASSERT_TRUE(dict->GetList("events", &events));
+  ASSERT_EQ(1u, events->GetSize());
+}
+
+TEST_F(NetLogLoggerTest, GeneratesValidJSONWithMultipleEvents) {
+  FILE* file = base::OpenFile(log_path_, "w");
+  ASSERT_TRUE(file);
+  scoped_ptr<base::Value> constants(NetLogLogger::GetConstants());
+  scoped_ptr<NetLogLogger> logger(new NetLogLogger(file, *constants));
+
+  const int kDummyId = 1;
+  NetLog::Source source(NetLog::SOURCE_SPDY_SESSION, kDummyId);
+  NetLog::EntryData entry_data(NetLog::TYPE_PROXY_SERVICE,
+                               source,
+                               NetLog::PHASE_BEGIN,
+                               base::TimeTicks::Now(),
+                               NULL);
+  NetLog::Entry entry(&entry_data, NetLog::LOG_ALL);
+
+  // Add the entry multiple times.
+  logger->OnAddEntry(entry);
+  logger->OnAddEntry(entry);
+  logger.reset();
+
+  std::string input;
+  ASSERT_TRUE(base::ReadFileToString(log_path_, &input));
+
+  base::JSONReader reader;
+  scoped_ptr<base::Value> root(reader.ReadToValue(input));
+  ASSERT_TRUE(root) << reader.GetErrorMessage();
+
+  base::DictionaryValue* dict;
+  ASSERT_TRUE(root->GetAsDictionary(&dict));
+  base::ListValue* events;
+  ASSERT_TRUE(dict->GetList("events", &events));
+  ASSERT_EQ(2u, events->GetSize());
+}
+
+}  // namespace
+
+}  // namespace net