This study indicates that the wastewater import of Hangu stabilization pond is very harmful to fish. A value of 24 Lc50 of the influent for siver carp (Hypophthalrnichys molitrix)carp(Cyprinus carpio)and crucian carp(Carassiws aur-atus)was measured as 3 %,30% and 58% in V/V respectively.Hangu stabilization pond has ability to self-purification for chemical industry wastewater. After stabilization, the water quality of pond was good for survival, growth and breeding of crucian carp.It isn't obvious for the c...