In this work, the nitrogen conversion factor in eggs Coturnix coturnix L. (Japanese quail), was determined. 850 eggs of Coturnix coturnix L. were analyzed, the maximum precipita-tion and extraction pH was determined by the Kjeldahl meth-od, at different acidic and basic pH. The protein conversion factors found for white and yolk were 6.33 and 6.30 respec-tively. These results justify its consumption compared to other food sources, high in protein in the human diet.