The first seven cases of cholera-like disease due to Vibrio parahaemolyticus, acquired mainly through handling of raw fish from the Indian Ocean, in Dar es Salaam are reported. Five of the patients were young women, two of those being fishmongers. The duration of the disease in six of the patients was short leading to recovery within 24 h. One of the patients took 4 days of intensive rehydration therapy before recovery. Whereas V. parahaemolyticus is the commonest cause of food poisoning in Japan where raw or half cooked salt water fish are a common delicacy, the disease in Tanzania where raw fish is almost never eaten, appears to have resulted mainly from poor personal hygiene in handling raw fish. It is recommended that more studies on the problem should be carried out and the public should be educated on the dangers of unhygienic handling of raw fish.