diff --git a/Lib/tkinter/simpledialog.py b/Lib/tkinter/simpledialog.py
index 85244171117b61..1927cf821bd6c7 100644
--- a/Lib/tkinter/simpledialog.py
+++ b/Lib/tkinter/simpledialog.py
@@ -260,7 +260,15 @@ def __init__(self, title, prompt,
                  parent = None):
 
         if not parent:
-            parent = tkinter._default_root
+            if tkinter._default_root:
+                parent = tkinter._default_root
+            elif tkinter._support_default_root:
+                parent = tkinter.Tk()
+                parent.withdraw()
+            else:
+                raise RuntimeError(
+                    "No parent specified and tkinter is "
+                    "configured to not support default root")
 
         self.prompt   = prompt
         self.minvalue = minvalue
diff --git a/Misc/NEWS.d/next/Core and Builtins/2019-12-31-19-06-02.bpo-39171.cmXDsX.rst b/Misc/NEWS.d/next/Core and Builtins/2019-12-31-19-06-02.bpo-39171.cmXDsX.rst
new file mode 100644
index 00000000000000..c3dfae4a2ad6e4
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2019-12-31-19-06-02.bpo-39171.cmXDsX.rst	
@@ -0,0 +1 @@
+Creating missing parent in tkinter simpledialog when possible.