The objective of this work was to determine the dietary protein requirement for broiler breeders during their breeding period. Two broiler breeder lines were submitted to isocaloric diets, with levels of crude protein (CP) of 12.0; 13.5; 15.0; 16.5 and 18.0% from 24th to 56th week of age. A linear effect of crude protein level on egg weight was observed only at the 32nd week of age. CP level did not affect the total number of eggs produced, bird live weight, and bird carcass composition. The results indicate that it is possible to use diets containing as little as 12% of CP for broiler breeder hens from the 24th to 56th week of age.