The effect of males and females breeder Japanese quail on egg production, fertility and hatchability of fertile eggs and on some behaviors (mating, resting, aggression, and feeding behaviors) and on feed consumption were studied. The results showed that , there was significant difference between groups in % of fertility and hatchability and infertility. The highest fertility and hatchability and lower dead embryo % werefound in LWxLW, followed by HWxHW. There was significant difference in egg production, LW laid more eggs than HW. HW laid heaviest eggs with highest albumen weight, shell weight and %were highest in eggs laid by LW. The highest % of soft shelled eggs were laid by HW. LW males completed more matings than HW, depending on the body size there was no difference between matings in groups of the relative body weight i.e. LW males completed more matings with LW females and the same was found with HW males and females. There was positive relationship between the number of attempts and % of completed matings. % of aggression directed from females to males was significantly higher than those directed from males to females depending on the body weight of females which is heaver than males. The heist was noted in groups of LW and HW. The % of birds drink , feed, and time spent at the feeder were higher at LWxHW. HW females rest more than LW ones. The daily feed consumption was higher in HW birds. Results suggest that LW males ranges from (130-160 g) and LW females ranges from (170-210 g) has best reproductive traits.