diff --git a/Doc/library/argparse.rst b/Doc/library/argparse.rst
index 1f40e4a84505d2..76efed95bd4ccb 100644
--- a/Doc/library/argparse.rst
+++ b/Doc/library/argparse.rst
@@ -1698,7 +1698,7 @@ Sub-commands
 
 .. method:: ArgumentParser.add_subparsers([title], [description], [prog], \
                                           [parser_class], [action], \
-                                          [option_string], [dest], [required], \
+                                          [option_strings], [dest], [required], \
                                           [help], [metavar])
 
    Many programs split up their functionality into a number of sub-commands,