This study deals with the physico-chemical characterization of wastewaters from the fish industry in Agadir city, Morocco. Seven samples were collected at every two hours from 8 a.m until 8 p.m. Three samplings were carried in this study accordingly: the first, on November 23(rd), 2005; the second, on February 23(rd), 2006 and the last one, on June 23(rd), 2006. The results indicated that the effluents show great variations in terms of conductivity (3.36-96.3 mS/ cm) and temperature (17-35 degrees C). The wastewaters were generally characterized by high amounts of chlorides, with average values of 9951.8 mg.L-1, and had BOD5 values between 1500-20500 mg.L-1, as well as COD values between 3500-26000 mg.L-1. Additionally, high amounts of total phosphor (total P), ammonium nitrogen (N-NH4), and total suspended solids (TSS) were observed. From the overall results, it can be said that the wastewaters from fish industry constitute a major environmental problem and must be taken into careful consideration.