diff --git a/doc/source/api.rst b/doc/source/api.rst
index caa5498db1ebf..56c4b2be51505 100644
--- a/doc/source/api.rst
+++ b/doc/source/api.rst
@@ -606,6 +606,7 @@ strings and apply several methods to it. These can be accessed like
        MultiIndex.str
        DatetimeIndex.str
        TimedeltaIndex.str
+       IntervalIndex.str
 
 
 .. _api.categorical: