diff --git a/filesystem_iterator_unittest.cc b/filesystem_iterator_unittest.cc
index fddde01..2ea3728 100644
--- a/filesystem_iterator_unittest.cc
+++ b/filesystem_iterator_unittest.cc
@@ -44,30 +44,42 @@
 
 TEST_F(FilesystemIteratorTest, RunAsRootSuccessTest) {
   ASSERT_EQ(0, getuid());
-  string first_image;
+
+  // Create uniquely named main/sub images.
+  string main_image;
   ASSERT_TRUE(utils::MakeTempFile("FilesystemIteratorTest.image1-XXXXXX",
-                                  &first_image, NULL));
+                                  &main_image, NULL));
+  ScopedPathUnlinker main_image_unlinker(main_image);
+
   string sub_image;
   ASSERT_TRUE(utils::MakeTempFile("FilesystemIteratorTest.image2-XXXXXX",
                                   &sub_image, NULL));
+  ScopedPathUnlinker sub_image_unlinker(sub_image);
+
+  // Create uniqely named main/sub mount points.
+  string main_image_mount_point;
+  ASSERT_TRUE(utils::MakeTempDirectory(
+          "/tmp/FilesystemIteratorTest.mount-XXXXXX",
+          &main_image_mount_point));
+  ScopedPathUnlinker main_image_mount_point_unlinker(main_image_mount_point);
+  const string sub_image_mount_point = main_image_mount_point + "/some_dir/mnt";
 
   vector<string> expected_paths_vector;
-  CreateExtImageAtPath(first_image, &expected_paths_vector);
+  CreateExtImageAtPath(main_image, &expected_paths_vector);
   CreateExtImageAtPath(sub_image, NULL);
-  ASSERT_EQ(0, System(string("mount -o loop ") + first_image + " " +
-                      kMountPath));
+  ASSERT_EQ(0, System(string("mount -o loop ") + main_image + " " +
+                      main_image_mount_point));
   ASSERT_EQ(0, System(string("mount -o loop ") + sub_image + " " +
-                      kMountPath + "/some_dir/mnt"));
+                      sub_image_mount_point));
   for (vector<string>::iterator it = expected_paths_vector.begin();
        it != expected_paths_vector.end(); ++it)
-    *it = kMountPath + *it;
+    *it = main_image_mount_point + *it;
   set<string> expected_paths(expected_paths_vector.begin(),
                              expected_paths_vector.end());
-  VerifyAllPaths(kMountPath, expected_paths);
+  VerifyAllPaths(main_image_mount_point, expected_paths);
 
-  EXPECT_TRUE(utils::UnmountFilesystem(kMountPath + string("/some_dir/mnt")));
-  EXPECT_TRUE(utils::UnmountFilesystem(kMountPath));
-  EXPECT_EQ(0, System(string("rm -f ") + first_image + " " + sub_image));
+  EXPECT_TRUE(utils::UnmountFilesystem(sub_image_mount_point));
+  EXPECT_TRUE(utils::UnmountFilesystem(main_image_mount_point));
 }
 
 TEST_F(FilesystemIteratorTest, NegativeTest) {
diff --git a/test_utils.cc b/test_utils.cc
index 5379979..b489cf1 100644
--- a/test_utils.cc
+++ b/test_utils.cc
@@ -28,6 +28,8 @@
 
 namespace chromeos_update_engine {
 
+const char* const kMountPathTemplate = "/tmp/UpdateEngineTests_mnt-XXXXXX";
+
 bool WriteFileVector(const std::string& path, const std::vector<char>& data) {
   return utils::WriteFile(path.c_str(), &data[0], data.size());
 }
@@ -193,31 +195,41 @@
 }
 
 void CreateExtImageAtPath(const string& path, vector<string>* out_paths) {
-  // create 10MiB sparse file
+  // create 10MiB sparse file, mounted at a unique location.
+  string mount_path;
+  CHECK(utils::MakeTempDirectory(kMountPathTemplate, &mount_path));
+  ScopedPathUnlinker mount_path_unlinker(mount_path);
+
   EXPECT_EQ(0, System(StringPrintf("dd if=/dev/zero of=%s"
                                    " seek=10485759 bs=1 count=1",
                                    path.c_str())));
   EXPECT_EQ(0, System(StringPrintf("mkfs.ext3 -b 4096 -F %s", path.c_str())));
-  EXPECT_EQ(0, System(StringPrintf("mkdir -p %s", kMountPath)));
   EXPECT_EQ(0, System(StringPrintf("mount -o loop %s %s", path.c_str(),
-                                   kMountPath)));
-  EXPECT_EQ(0, System(StringPrintf("echo hi > %s/hi", kMountPath)));
-  EXPECT_EQ(0, System(StringPrintf("echo hello > %s/hello", kMountPath)));
-  EXPECT_EQ(0, System(StringPrintf("mkdir %s/some_dir", kMountPath)));
-  EXPECT_EQ(0, System(StringPrintf("mkdir %s/some_dir/empty_dir", kMountPath)));
-  EXPECT_EQ(0, System(StringPrintf("mkdir %s/some_dir/mnt", kMountPath)));
-  EXPECT_EQ(0, System(StringPrintf("echo T > %s/some_dir/test", kMountPath)));
-  EXPECT_EQ(0, System(StringPrintf("mkfifo %s/some_dir/fifo", kMountPath)));
-  EXPECT_EQ(0, System(StringPrintf("mknod %s/cdev c 2 3", kMountPath)));
-  EXPECT_EQ(0, System(StringPrintf("ln -s /some/target %s/sym", kMountPath)));
+                                   mount_path.c_str())));
+  EXPECT_EQ(0, System(StringPrintf("echo hi > %s/hi", mount_path.c_str())));
+  EXPECT_EQ(0, System(StringPrintf("echo hello > %s/hello",
+                                   mount_path.c_str())));
+  EXPECT_EQ(0, System(StringPrintf("mkdir %s/some_dir", mount_path.c_str())));
+  EXPECT_EQ(0, System(StringPrintf("mkdir %s/some_dir/empty_dir",
+                                   mount_path.c_str())));
+  EXPECT_EQ(0, System(StringPrintf("mkdir %s/some_dir/mnt",
+                                   mount_path.c_str())));
+  EXPECT_EQ(0, System(StringPrintf("echo T > %s/some_dir/test",
+                                   mount_path.c_str())));
+  EXPECT_EQ(0, System(StringPrintf("mkfifo %s/some_dir/fifo",
+                                   mount_path.c_str())));
+  EXPECT_EQ(0, System(StringPrintf("mknod %s/cdev c 2 3", mount_path.c_str())));
+  EXPECT_EQ(0, System(StringPrintf("ln -s /some/target %s/sym",
+                                   mount_path.c_str())));
   EXPECT_EQ(0, System(StringPrintf("ln %s/some_dir/test %s/testlink",
-                                   kMountPath, kMountPath)));
-  EXPECT_EQ(0, System(StringPrintf("echo T > %s/srchardlink0", kMountPath)));
+                                   mount_path.c_str(), mount_path.c_str())));
+  EXPECT_EQ(0, System(StringPrintf("echo T > %s/srchardlink0",
+                                   mount_path.c_str())));
   EXPECT_EQ(0, System(StringPrintf("ln %s/srchardlink0 %s/srchardlink1",
-                                   kMountPath, kMountPath)));
+                                   mount_path.c_str(), mount_path.c_str())));
   EXPECT_EQ(0, System(StringPrintf("ln -s bogus %s/boguslink",
-                                   kMountPath)));
-  EXPECT_TRUE(utils::UnmountFilesystem(kMountPath));
+                                   mount_path.c_str())));
+  EXPECT_TRUE(utils::UnmountFilesystem(mount_path.c_str()));
 
   if (out_paths) {
     out_paths->clear();
diff --git a/test_utils.h b/test_utils.h
index 6d3c5bd..2b72af1 100644
--- a/test_utils.h
+++ b/test_utils.h
@@ -112,7 +112,6 @@
   0xbe, 0x9f, 0xa3, 0x5d
 };
 
-const char* const kMountPath = "/tmp/UpdateEngineTests_mnt";
 }  // namespace {}
 
 // Creates an empty ext image.