Ovulation in chicken is the process of emergence the egg yolk by controlling the steroid hormones, which is followed by oviposition that influence by several factors. Egg yolk is a huge oocyte contains fat in water emulsion with about 50% dry weight, its rounded and centrally located. The experiment was carried out to investigate the effect of oviposition time on egg external traits (egg weight, egg length, egg breadth), yolk characteristics (yolk weight, yolk high, yolk diameter, yolk index, and the proportion of yolk weight to egg whole weight), and investigate the correlations between these characteristics by using Ross 308 hybrid.When the flock was 30 weeks age, 150 fertilizes egg was used, which collected in three times, Period (1) = 9:30 am, Period (2) = 11:30 am, and Period (3) = 1:30 pm, which supplied from KOSAR company.The results reveal significant differences between the times of collection for all the yolk characteristics and egg external traits.It does conclude the yolk characteristics were differs significantly between the oviposition times and the yolk weight was highly correlated with yolk diameter, egg breadth, and proportion of yolk weight to the whole egg weight.