The aim of this study was to determine the pathological effects of formalin on female quails. Seventy-five 1-day-old female Japanese quails (Coturnix coturnix japonina) were divided into five equal groups (A-E) and fed formalin daily at dose levels of 20, 10, 5, 2.5 and 0 mL/ kg feed, respectively. All birds were slaughtered at the end of the experiment -- the eighth week. No clinical signs were observed in quails fed 2.5 mL formalin/kg feed. Depression, dullness and anorexia were prominent in quails fed 20 mL formalin/kg feed. Feed intake, body weight, egg production and egg weight together with absolute and relative weight of organs, erythrocyte and leukocyte counts, hemoglobin concentration and hematocrit were decreased at higher doses, i.e., 10 and 20 mL formalin/kg feed. Total serum proteins and globulin significantly increased (P <0.05) in all formalin fed quails compared to control birds. No gross lesions were observed in the 2.5 mL formalin/kg fed group. At higher doses (10 and 20 mL formalin/kg feed) hemorrhages on the thigh muscles, decreased weight and reduction in area and folds of different segments of oviduct were recorded. Reduced size of liver, heart and kidneys was recorded in quails fed 20mL formalin/kg feed compared to controls and other birds. The histopathological changes in oviduct consisted of degeneration of mucosal glands characterized by vacuolation of nuclei of cells. It was concluded from the study that formalin feeding to female quails at 2.5 mL/kg feed is without harmful effects, however, higher doses are not without health risks.