Abstract: Three forms of silver (Ag⁺, Ag (S₂O₃)₂^3-, AgBr) have been selected in the static experiment of purification of silver-bearing waste water from cinefilm processing factory by water hyacinth. The results indication that silver removal rates from SBWW within 24 hours were 0. 136, 0. 054 and 0. 030 for Ag⁺, Ag (S₂O₃)₂^3-and AgBr respectively. The purification rate relate mainly with detention time(t),original silver concentration,silver form,tempera ture and pH. In addition, the results of dynamic simulated experiment with Ag (S₂O₃)₂^3- indicate that the relationship between purification rate (R) and detention time (t) is R=Ae^R/t (B<0), Relationship between surface purification rate (Ps) and detention time (t) is Ps=At^R (B<0).