diff --git a/dvc/state.py b/dvc/state.py
index 2eb01750c..655d9dfd9 100644
--- a/dvc/state.py
+++ b/dvc/state.py
@@ -245,26 +245,18 @@ class State(object):
 
     @staticmethod
     def mtime_and_size(path):
+        size = os.path.getsize(path)
         mtime = os.path.getmtime(path)
 
         if os.path.isdir(path):
-            size = 0
             for root, dirs, files in os.walk(path):
-                for dname in dirs:
-                    p = os.path.join(root, dname)
-                    m = os.path.getmtime(p)
-                    if m > mtime:
-                        mtime = m
-
-                for fname in files:
-                    p = os.path.join(root, fname)
+                for name in dirs + files:
+                    p = os.path.join(root, name)
                     st = os.stat(p)
                     size += st.st_size
                     m = st.st_mtime
                     if m > mtime:
                         mtime = m
-        else:
-            size = os.path.getsize(path)
 
         # State of files handled by dvc is stored in db as TEXT.
         # We cast results to string for later comparisons with stored values.
diff --git a/tests/unit/state.py b/tests/unit/state.py
index 633424bcf..18d6060a6 100644
--- a/tests/unit/state.py
+++ b/tests/unit/state.py
@@ -10,7 +10,9 @@ class TestMtimeAndSize(TestDvc):
         dir_time, dir_size = State.mtime_and_size(self.DATA_DIR)
 
         actual_file_size = os.path.getsize(self.DATA)
-        actual_dir_size = (os.path.getsize(self.DATA)
+        actual_dir_size = (os.path.getsize(self.DATA_DIR)
+                           + os.path.getsize(self.DATA)
+                           + os.path.getsize(self.DATA_SUB_DIR)
                            + os.path.getsize(self.DATA_SUB))
 
         self.assertIs(type(file_time), str)