The present experiment was executed to determine the pathological effects induced by concurrent feeding of butachlor (chloroacetanilide herbicide) in male Japanese quail. For this purpose mature male quail about 4-5weeks of age were procured from the local market and randomly divided into six equal groups (A-F). Butachlor was mixed in corn oil and administered orally for 30days using crop tube. Four birds from each group were killed at day 10, 20 and 30 of the experiment and blood was collected with and without anticoagulant. The birds in groups (A-D) did not reveal any clinical and behavioral alterations. Clinical signs like watery droppings, dullness, ruffled feather, depression, decrease frequency of crowing, mounting with pen mates and foam production were observed. Maximum intensity of these clinical signs and behavioral alterations were observed in group F throughout the experiment. Significant lower values of erythrocytes, hematocrit percent and hemoglobin were recorded. Significantly increased numbers of erythrocytes with micronuclei, lobed and notched nuclei were observed. Histopathologically, enlarged intertubular space, fewer numbers of round spermatids, necrotic spermatids and admixture of dead spermatids were observed in testes. The results revealed significant increase in serum lactate dehydrogenase (LDH), aspartate transaminase (AST), alanine transaminase (ALT) and urea concentrations. The results of present experimental study indicated that butachlor induces hematobiochemical and testicular changes in birds.