The aim of this study is to investigate the effects of adding different doses of boric acid (H3BO3) to the mixed feed of Japanese quail (Coturnix coturnix Japonica) on fattening performance, carcass and bone properties. For this purpose, a total of 96 quails aged 15 days were balanced according to their live weight and sex, and 4 trials were randomly divided into groups. Each group is composed of 4 repetitions. Trial groups; the control group (C) given mixed feed, the group with 100 mg / kg boric acid (BA) added to the feed BA100; 300 mg / kg boric acid was added to the feed group BA300 and 500 mg / kg boric acid added to the feed group BA500. Data for the fattening period were followed for 15-43 days. At the end of the experiment, carcass and bone characteristics of 8 quails (two quails from each repeat) from each group were examined. The live weight and live weight gain of the quail was similar among the experimental groups (P>0.05). Adding boric acid to feed did not affect feed consumption and feed utilization rate (P>0.05). While the breast rate decreased significantly due to the increasing levels of boric acid addition (P<0.01), an increase in the back and neck ratio was detected (P <0.05). The highest thigh ratio was found in BA300 and BA500 groups (P<0.05). Carcass yield, wing and liver rates were similar between the groups (P>0.05). Tibia and femur weights and dimensions were not affected by the addition of boric acid (P>0.05). The highest femoral ash level was determined in the BA300 group (P=0.05). The tibia ash level increased from the Control group towards BA300 and was the lowest in the BA500 group (P<0.05). As a result, while the addition of boric acid to the feed cannot be affected to the fattening performance of quail, its effect on carcass and bone properties has been found significant.