This study aims to determine the weight ratio for crossbreeding between male brood of Clarias nieuhofii and female brood of Clarias batrachus . The observation of the fertilized eggs, shows that: Treatment C, fertilized eggs reached (89%); treatment B (86%), and treatment A (63%). It showed that the ratio of male and female parent was very significant effect on the success of fertilization, as well as on the level of hatching eggs: Treatment of C (38.202%); B (33.72%); and A (15.87%). Survival rate of crossbred seeds had a level of normalcy: 83.335%. The results of this study prove that this crossbreeding is feasible to do. Key words : Clarias nieuhofii, Clarias batrachus, cross breeding, hatching egg.