Guadalupe Creek is a northward-flowing stream originating just east of the peak of Mount Umunhum in Santa Clara County, California, United States. It courses along the northwestern border of Almaden Quicksilver County Park in the Cañada de los Capitancillos before joining Los Alamitos Creek after the latter exits Lake Almaden. This confluence forms the Guadalupe River mainstem, which in turn flows through San Jose and empties into south San Francisco Bay at Alviso Slough.