diff --git a/pkg/private/tar/build_tar.py b/pkg/private/tar/build_tar.py
index ab16610d..b6b75bd7 100644
--- a/pkg/private/tar/build_tar.py
+++ b/pkg/private/tar/build_tar.py
@@ -309,7 +309,10 @@ def add_manifest_entry(self, entry_list, file_attributes):
     elif entry.entry_type == manifest.ENTRY_IS_EMPTY_FILE:
       self.add_empty_file(entry.dest, **attrs)
     else:
-      self.add_file(entry.src, entry.dest, **attrs)
+      if os.path.isdir(entry.src):
+        self.add_tree(entry.src, entry.dest, **attrs)
+      else:
+        self.add_file(entry.src, entry.dest, **attrs)
 
 
 def main():
diff --git a/tests/tar/BUILD b/tests/tar/BUILD
index 19504e1c..22d6c6ef 100644
--- a/tests/tar/BUILD
+++ b/tests/tar/BUILD
@@ -60,6 +60,20 @@ genrule(
     cmd = "for i in $(OUTS); do echo 1 >$$i; done",
 )
 
+genrule(
+    name = "generate_dir_file",
+    outs = ["lib"],
+    cmd = "mkdir -p $@; echo 1 >$@/nsswitch.conf",
+)
+
+pkg_tar(
+    name = "test_tar_dir_file",
+    srcs = [
+        ":generate_dir_file",
+    ],
+    out = "dir_file.tar",
+)
+
 directory(
     name = "generate_tree",
     contents = "hello there",