The Caspian kutum or Caspian white fish is a species of ray-finned fish belonging to the family Leuciscidae,. It lives in the brackish water habitats of the Caspian Sea and its freshwater tributaries. It is typically a medium-sized fish, reaching 45–55 cm in length, rarely 70 cm, and weighing up to 4.00 kg, rarely 5.00 kg. It used to be very common and was harvested commercially. The population seems to have collapsed due to overfishing and marine pollution. Its flesh and roe are enjoyed as food, and highly prized in the Gilan and Mazandaran provinces in Iran.