An updated checklist of the freshwater decapod species of Puerto Rico is presented based on records of shrimp and crab species whose presence has been confirmed in Puerto Rico as a result of extensive field collections, examination of carcinological collections, literature review, and personal communications from researchers. The freshwater decapods fauna of Puerto Rico consists of 18 species of shrimps belonging to eight genera and three families, and one species of crab belonging to the family Pseudothelphusidae.