The present study was conducted to analyze the taxonomic aspects of percoid fishes of Manimala River of Travancore, Kerala, India. Systematic studies were conducted on the fishes of the genera Ambassis, Parambassis, Etroplus, Pseudetroplus, Pristolepis, Anabas, Channa, Glossogobius, Awaous and Pseudosphromenus. The fishes were examined for meristic counts and metric characters and various taxonomic aspects were discussed.