7 species ef fish and aqutic animal samples (silver carp, Tilapia,common carp, crucian carp, wooly handed crab, Cambarus and Tadpole)were bought and tested for the toxicity of Ag⁺. Meanwhile fish samples were caught from theoxidation pond of cine--film factory in Wuxi for analysing the concentraction ofAg⁺. The results indicated that: (1) All of these aquatic animals were toxicated by Ag⁺ at different degrees. LC₅₀ of Ag⁺ to their fries is within 2-40 ppb. Among themthe fry of silver carp is most sensitive to Ag⁺. But sensitivity of adult fish to Ag⁺ismuch lower than that of fries. (2) Viscera of bottom fish, e. g. crucian carp has thehighest consent of silver,and its concentration is about 144.07 ppm(DM) ,while theaccumulation times is 14407. Gill of upper layer fish, e.g. Haniculter has the contentabout 15.95ppm(DM), and the accumulation times is 1595. Mucle in all of fishsamples has lowest content of silver.