A study was conducted to determine the effect of divergent selection for 35-day body weight on some reproductive traits of Japanese quail. A total of 1,500 chicks obtained from the National Veterinary Research Institute in Vom, Plateau State served as the base population from which ‘High Line’ and ‘Low Line’ were established based on individual body weight at 35-days of age. A random sample of the base population was maintained as the Control Line. Random mating was made within Line at the ratio of one male to three females and eggs were collected for incubation to produce subsequent generations using the same selection procedure. Data obtained on age at first egg, body weight at first egg, fertility and hatchability over five generations of selection were analysed within and between Lines using One-way Analysis of Variance procedure. The High body weight Line attained sexual maturity at a significantly (P<0.05) lower age (40.56 days) than the Low body weight Line which reached sexual maturity at 59.78 days. Body weight at sexual maturity was highest in the High body weight Line (143.63g) followed by the Control (133.64g) and lowest in the Low body weight Line (113.33g). Percentage fertility of incubated eggs showed no significant (P>0.05) differences among experimental lines in all generations except generation four. Over the five generations of selection, the Low weight lines had the highest fertility (86.07%). Percent hatchability over the five generations of selections in the three lines showed no significant (P>0.05) differences though the High body weight line had the highest mean value (44.37%). Mean hatchability of fertile eggs for the five generations of selection was highest in the High Body Weight line (53.18%) though not significantly (P>0.05) higher than the Control (50.86%), and the Low line (43.49%). Hatch weight increased with progress in selection. At the end of five generations, mean hatch weight differed significantly (P<0.05). Mean values were 6.42g, 6.08g and 5.79g for the High Control and the Low lines respectively. Chick: Egg weight ratios were not significantly (P>0.05) affected in all generations, though there was an increase with progress in selection in the High line. The results showed that selection for high 35-day body weight is desirable to improve the hatchability, chick weight and age at sexual maturity in Japanese quail. 1499089481.php