The main objective of the experiment was to study heterosis ef-fect on some egg production traits in two lines of Node layers (i.e. heavy , HOW and light body weight , LBW) The results and conclusion can be summarized as follows : 1. The heterosis estimates were 5.2 and - 1.5 % for body weight at sex-ual maturity In HBW x LBW and LBW x H8W crosses, respectively, white, the corresponding estimates of body weight at maturity were 9.7 and 4.5 %, respectively. It was clear that, crossing between lines is considered an effective method to increase body weight in chick‌ens. 2. Sexual maturity was 166.4 , 176.2 and 172.6 d. for heavy , light and control, respectively. It was noticed that, LBW x HOW cross had sexu‌al maturity equal to 169.5 d., while, it was 173 and 172.6 d. in HBW x LBW and control, respectively. The heterosis effects were 1.0 and -1.1 % for HBW x LBW and LBW x HBW crosses. respectively. It was clear that, both of selection and line crossing are useful tool to de‌crease age at sexual maturity. 3. At maturity. heterosis effects of egg weight as deviation from paren‌tal means were 5.8 and 1.7 % for HOW x LBW and LOW x HOW cross‌es. respectively. 4. Breast width is positively correlated with body weight. The results of breast width were promising, and selection for improving this trait or crossing among different strains were considered effective methods to increase it. 5. At 52-weeks of age, the means of egg number of pure groups were 117.4 , 109.9 and 105.6 eggs for heavy , light and control lines. white, HBW x LBW and LBW x HBW crosses were intermediate be‌tween the figures of the parents and control.