diff --git a/Lib/test/test_urlparse.py b/Lib/test/test_urlparse.py
index 80fb9e5cd2a445..661bc4642f41a1 100644
--- a/Lib/test/test_urlparse.py
+++ b/Lib/test/test_urlparse.py
@@ -437,6 +437,12 @@ def test_urljoins(self):
         # issue 23703: don't duplicate filename
         self.checkJoin('a', 'b', 'b')
 
+        # issue 32779: clear the query string when joining with '?'
+        self.checkJoin('http://a/b/c?d=e', '?', 'http://a/b/c')
+        self.checkJoin('http://a/b/c?d=e', 'http:?', 'http://a/b/c')
+        self.checkJoin('http://a/b/c#d?e=f', '?#g', 'http://a/b/c#g')
+        self.checkJoin('http://a/b/c?d=e#f', '#?', 'http://a/b/c?d=e#?')
+
     def test_RFC2732(self):
         str_cases = [
             ('http://Test.python.org:5432/foo/', 'test.python.org', 5432),
diff --git a/Lib/urllib/parse.py b/Lib/urllib/parse.py
index 5f95c5ff7f9c1c..1908642e8b1e16 100644
--- a/Lib/urllib/parse.py
+++ b/Lib/urllib/parse.py
@@ -535,7 +535,10 @@ def urljoin(base, url, allow_fragments=True):
     if not path and not params:
         path = bpath
         params = bparams
-        if not query:
+        # since urlparse doesn't leave any evidence of whether there was a bare
+        # '?' with an empty query string, we need to check whether it was there.
+        has_empty_query = url[0] == '?' or url.startswith(scheme + ':?')
+        if not has_empty_query:
             query = bquery
         return _coerce_result(urlunparse((scheme, netloc, path,
                                           params, query, fragment)))
diff --git a/Misc/NEWS.d/next/Library/2018-02-12-17-12-45.bpo-32779.FYzcZd.rst b/Misc/NEWS.d/next/Library/2018-02-12-17-12-45.bpo-32779.FYzcZd.rst
new file mode 100644
index 00000000000000..6729499008d9f0
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2018-02-12-17-12-45.bpo-32779.FYzcZd.rst
@@ -0,0 +1 @@
+Fix urljoining with '?', a URL containing only a bare query string.