[Background] Interspecific competition in the family Tephritidae (fruit flies) can happen at every developmental stage of the life cycle. However, interspecific competition during egg and pupa stages of two fruit flies has not been observed.[Method] Bactrocera dorsalis and B. correcta were reared together under different proportions and time of introduction of the second species. The developmental duration and survival rate of the two species were then measured.[Result] There were no effects on the duration of the egg stage and hatching rate of both species when eggs of B. dorsalis and B. correcta were initially mixed in equal numbers and at the same egg age. However, when pupae of different ages (one new and one of one day old) of the two fruit flies were mixed, emergence rates of the younger pupae were respectively (87.67±3.61)% for B. dorsalis and (84.33±2.56)% for B. correcta, which were significantly less than the respective controls. This outcome implied that the younger pupae could inhibit the growth by the older pupae.[Conclusion and significance] The study shows that interspecific competitive effect between B. dorsalis and B. correcta is minimal with a possibility of competition at the pupal stage.