diff --git a/Doc/library/urllib.parse.rst b/Doc/library/urllib.parse.rst
index 49276daa7ff..84d289bc441 100644
--- a/Doc/library/urllib.parse.rst
+++ b/Doc/library/urllib.parse.rst
@@ -571,7 +571,7 @@ task isn't already covered by the URL parsing functions above.
    percent-encoded sequences into Unicode characters, as accepted by the
    :meth:`bytes.decode` method.
 
-   *string* must be a :class:`str`.
+   *string* may be either a :class:`str` or a :class:`bytes`.
 
    *encoding* defaults to ``'utf-8'``.
    *errors* defaults to ``'replace'``, meaning invalid sequences are replaced
@@ -579,6 +579,11 @@ task isn't already covered by the URL parsing functions above.
 
    Example: ``unquote('/El%20Ni%C3%B1o/')`` yields ``'/El Niño/'``.
 
+   .. versionchanged:: 3.9
+      *string* parameter supports bytes and str objects (previously only str).
+
+
+
 
 .. function:: unquote_plus(string, encoding='utf-8', errors='replace')
 
diff --git a/Lib/test/test_urllib.py b/Lib/test/test_urllib.py
index 9a6b5f66b7a..3f59c660845 100644
--- a/Lib/test/test_urllib.py
+++ b/Lib/test/test_urllib.py
@@ -1049,8 +1049,6 @@ class UnquotingTests(unittest.TestCase):
                          "%s" % result)
         self.assertRaises((TypeError, AttributeError), urllib.parse.unquote, None)
         self.assertRaises((TypeError, AttributeError), urllib.parse.unquote, ())
-        with support.check_warnings(('', BytesWarning), quiet=True):
-            self.assertRaises((TypeError, AttributeError), urllib.parse.unquote, b'')
 
     def test_unquoting_badpercent(self):
         # Test unquoting on bad percent-escapes
@@ -1210,6 +1208,29 @@ class UnquotingTests(unittest.TestCase):
         self.assertEqual(expect, result,
                          "using unquote(): %r != %r" % (expect, result))
 
+    def test_unquoting_with_bytes_input(self):
+        # ASCII characters decoded to a string
+        given = b'blueberryjam'
+        expect = 'blueberryjam'
+        result = urllib.parse.unquote(given)
+        self.assertEqual(expect, result,
+                         "using unquote(): %r != %r" % (expect, result))
+
+        # A mix of non-ASCII hex-encoded characters and ASCII characters
+        given = b'bl\xc3\xa5b\xc3\xa6rsyltet\xc3\xb8y'
+        expect = 'bl\u00e5b\u00e6rsyltet\u00f8y'
+        result = urllib.parse.unquote(given)
+        self.assertEqual(expect, result,
+                         "using unquote(): %r != %r" % (expect, result))
+
+        # A mix of non-ASCII percent-encoded characters and ASCII characters
+        given = b'bl%c3%a5b%c3%a6rsyltet%c3%b8j'
+        expect = 'bl\u00e5b\u00e6rsyltet\u00f8j'
+        result = urllib.parse.unquote(given)
+        self.assertEqual(expect, result,
+                         "using unquote(): %r != %r" % (expect, result))
+
+
 class urlencode_Tests(unittest.TestCase):
     """Tests for urlencode()"""
 
diff --git a/Lib/urllib/parse.py b/Lib/urllib/parse.py
index b6608783a89..3a38dc14c90 100644
--- a/Lib/urllib/parse.py
+++ b/Lib/urllib/parse.py
@@ -631,6 +631,8 @@ def unquote(string, encoding='utf-8', errors='replace'):
 
     unquote('abc%20def') -> 'abc def'.
     """
+    if isinstance(string, bytes):
+        return unquote_to_bytes(string).decode(encoding, errors)
     if '%' not in string:
         string.split
         return string
diff --git a/Misc/NEWS.d/next/Library/2018-06-17-21-02-25.bpo-32498.La3TZz.rst b/Misc/NEWS.d/next/Library/2018-06-17-21-02-25.bpo-32498.La3TZz.rst
new file mode 100644
index 00000000000..9df9e65e55b
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2018-06-17-21-02-25.bpo-32498.La3TZz.rst
@@ -0,0 +1,2 @@
+Made :func:`urllib.parse.unquote()` accept bytes in addition to strings.
+Patch by Stein Karlsen.