diff --git a/jedi/api/file_name.py b/jedi/api/file_name.py
index 7df53294..de4e74cc 100644
--- a/jedi/api/file_name.py
+++ b/jedi/api/file_name.py
@@ -4,6 +4,7 @@ from jedi._compatibility import FileNotFoundError, force_unicode
 from jedi.evaluate.names import AbstractArbitraryName
 from jedi.api import classes
 from jedi.evaluate.helpers import get_str_or_none
+from jedi.parser_utils import get_string_quote
 
 
 def file_name_completions(evaluator, module_context, start_leaf, string, like_name):
@@ -29,7 +30,13 @@ def file_name_completions(evaluator, module_context, start_leaf, string, like_na
     for name in listed:
         if name.startswith(must_start_with):
             path_for_name = os.path.join(base_path, name)
-            if os.path.isdir(path_for_name) and not is_in_os_path_join:
+            if is_in_os_path_join:
+                if start_leaf.type == 'string':
+                    name += get_string_quote(start_leaf)
+                else:
+                    assert start_leaf.type == 'error_leaf'
+                    name += start_leaf.value
+            elif os.path.isdir(path_for_name):
                 name += os.path.sep
 
             yield classes.Completion(
@@ -103,7 +110,6 @@ def _maybe_add_os_path_join(module_context, start_leaf, string):
     arglist = start_leaf.parent
     index = arglist.children.index(start_leaf)
     arglist_nodes = arglist.children[:index]
-    print(arglist, arglist_nodes)
     if start_leaf.type == 'error_leaf':
         # Unfinished string literal, like `join('`
         if index > 0:
diff --git a/jedi/parser_utils.py b/jedi/parser_utils.py
index 6b590112..99d7a96b 100644
--- a/jedi/parser_utils.py
+++ b/jedi/parser_utils.py
@@ -291,3 +291,7 @@ def cut_value_at_position(leaf, position):
         column -= leaf.column
     lines[-1] = lines[-1][:column]
     return ''.join(lines)
+
+
+def get_string_quote(leaf):
+    return re.match('\w*("""|\'{3}|"|\')', leaf.value).group(1)
diff --git a/test/test_api/test_completion.py b/test/test_api/test_completion.py
index 983efe1c..58ae0f2d 100644
--- a/test/test_api/test_completion.py
+++ b/test/test_api/test_completion.py
@@ -210,20 +210,20 @@ os_path = 'from os.path import *\n'
         (f2, os_path + 'dirname(__file__) + "%stest_ca' % s, None, ['che.py']),
         (f2, os_path + 'dirname(abspath(__file__)) + sep + "test_ca', None, ['che.py']),
         (f2, os_path + 'join(dirname(__file__), "completion") + sep + "basi', None, ['c.py']),
-        (f2, os_path + 'join(dirname(__file__), "completion", "basi', None, ['c.py']),
-        (f2, os_path + 'join(dirname(__file__), "completion", "basi)', 43, ['c.py']),
-        (f2, os_path + 'join(dirname(__file__), "completion", "basi")', 43, ['c.py']),
-        (f2, os_path + 'join(dirname(__file__), "completion", "basi)', 35, ['']),
-        (f2, os_path + 'join(dirname(__file__), "completion", "basi)', 33, ['on']),
-        (f2, os_path + 'join(dirname(__file__), "completion", "basi")', 33, ['on']),
+        (f2, os_path + 'join(dirname(__file__), "completion", "basi', None, ['c.py"']),
+        (f2, os_path + 'join(dirname(__file__), "completion", "basi)', 43, ['c.py"']),
+        (f2, os_path + 'join(dirname(__file__), "completion", "basi")', 43, ['c.py"']),
+        (f2, os_path + 'join(dirname(__file__), "completion", "basi)', 35, ['"']),
+        (f2, os_path + 'join(dirname(__file__), "completion", "basi)', 33, ['on"']),
+        (f2, os_path + 'join(dirname(__file__), "completion", "basi")', 33, ['on"']),
 
         # join with one argument. join will not get evaluated and the result is
         # that directories and in a slash. This is unfortunate, but doesn't
         # really matter.
-        (f2, os_path + 'join("tes', 9, ['t']),
-        (f2, os_path + 'join("tes)', 9, ['t']),
-        (f2, os_path + 'join("tes"', 9, ['t']),
-        (f2, os_path + 'join("tes")', 9, ['t']),
+        (f2, os_path + 'join("tes', 9, ['t"']),
+        (f2, os_path + 'join(\'tes)', 9, ["t'"]),
+        (f2, os_path + 'join(r"tes"', 10, ['t"']),
+        (f2, os_path + 'join("""tes""")', 11, ['t"""']),
     ]
 )
 def test_file_path_completions(Script, file, code, column, expected):