The purpose of this study is 10 determine the relationships between body weight and age of sexual maturity in broiler breeders and to determine the effects of housmg together male and female broiler parents with different body weight at 22 weeks old age during production period on mortality. egg production, egg weight, hatchablity. fertility. As the research material, 778 Avian female and 116 Peterson male broiler breeders were used. Parent male and female chickens were separately divided into three base body weight groups called light. middle and heavy at 22 weeks old age. Separately three body weight subgroups which have almost Similar variance and average values were obtained from base body weight groups by using sensilive sampling method. Six male and 64 female broiler breeder parent chickens obtained from bodyweight subgroups were housed In 9 pens during production period. Egg produclion percentage, egg weight, hatchability, fertility, age at sexual maturity of broiler breeder chicken groups were determined. Age at onset of lay of Hh (light male x light female), Ha, Ho, Ah, Aa(Heavy male x heavy female). Ao, Oh, Oa and Oo(Middle male x middle female) broiter breeder female groups were determined as t 86, t79, 181, 186, t73. t81. 184, 176, and 180 days, respectively. There were no statistically significant differences among broiler bre· eder parent groups in respects of average production period egg production percentage, egg weight, fertility and hatchability. As a result, it can be said that there were need 10 investigate the effect of body weight trait 01 different mating groups at sexual maturity age in broiler breeders on the performance of their olfsprings.