In China, people believe that ingestion of fish gall bladder may improve their visual acuity. However, poisoning cases are of frequent occurrence when people ingest fish bile. In a long term, the intoxication of fish gall bladder is seriously threatening the victims'lives and health. In the past 35 years from 1964 to 1999, according to incomplete statistics 451 persons suffered poisoning for swallowing the gall bladder of cyprinds, among which 83 resulted in death. The death rate is 18.04%. This paper deals with the introduction of the conditions on gall bladder poisonous fish in China, the components of toxic substances (cyprinol) of bile juice, the animal experiment of acute intoxication, symptom of poisoning and treatment of victims. After the animal experiments and investigation, 12 species of freshwater fishes have been found to contain toxins in their gall bladders. These species all belong to the family of Cyprinidae. These results theoretically show that it is dangerous to swallow any bile juices of cyprinids fishes.