Six hundred Vanaraja hatching eggs were incubated in forced draft incubator in three groups of 200 eggs each. Group I(T1) was incubated normally while as group II(T2) and III(T3) were subjected to cold conditioning on days 5th and 18th respectively by holding them at room temperature for 1 hour. On 18th day of incubation candling was done. The infertile eggs were broken to check at which stage growth was arrested (early, mid and late embryonic mortality).The hatchability was also determined as HTES (Hatchability on Total Eggs Set) and HFES (Hatchability on Fertile Eggs Set). On the day of hatch, unhatched eggs were broken to find out the stage of mortality and no. of crippled chicks were also calculated. The data was analysed and results thus obtained showed no significant difference in any of the groups with respect to fertility, hatchability (HTES and HFES), no. of crippled chicks and total embryonic mortality. But early, mid and late embryonic mortality within a particular group showed significant difference with late embryonic mortality being highest within the group as well as between the groups with the highest late embryonic mortality in T3 group.