Crooked Creek is a tributary of the Allegheny River in both Armstrong and Indiana counties in the U.S. state of Pennsylvania. Several covered bridges span the stream and its tributaries in Indiana County. The Thomas Covered Bridge crosses Crooked Creek in Armstrong Township. The Harmon's Covered Bridge crosses the South Branch Plum Creek and the Trusal Covered Bridge crosses Plum Creek, tributaries of Crooked Creek, in Washington Township.