In this study, first was primarily to determine the effects of acute toxicity of the agricultural toxicant diazinon (emulsion 60%) on kutum male broodstocks. For this purpose, 4 treatments were used to toxicity test. Each treatment was repeated in 3 tanks with 9 fish per treatment and with 180 litres water capacity. After obtaining the final results, the information was analysed statistically and determined the LC10, LC50 and LC90 values at 24, 48, 72 and 96 hours. Were determined maximum allowable concentration value and the degree of toxicity. The second stage of testing consists of 4 treatments and male brood stocks of kutum were treated for 45 days. For analysis of all data SPSS version 13 was used. The results showed that the 96h LC50 value of diazinon was 0.4 mgl-1 and that the maximum allowable concentration (MAC) value of this toxin was 0.04 mgl-1. Our results show that diazinon causes a decrease in the erythrocyte count (RBC), haemoglobin (Hb), haematocrit (Hct), Mean Corpuscular Volume (MCV), Mean Corpuscular Haemoglobin (MCH), Mean Corpuscular Haemoglobin Concentration (MCHC), leucocyte count (WBC) and lymphocyte. In addition, diazinon also causes an increase in prolymphocyte (P<0.05). There are no significant effects on monocyte and eosinophil levels in kutum male broodstocks (P>0.05).