[Objectives]  To provide a theoretical basis for the use of ⁶⁰Co-γ ray irradiation to control Grapholita molesta.  [Methods]  Male G. molesta pupae were irradiated with 0, 25, 50, 75 Gy of  ⁶⁰Co-γ rays one day before emergence and the effects on adult emergence rate, fertility and longevity, were analyzed. [Results]  There was no significant difference in the adult emergence rate, or mating rate, of irradiated and control adults. The number of eggs laid by adult females mated with irradiated males was also not significantly different to that of females that mated with non-irradiated males. However, the hatching rate of eggs laid by females that mated with irradiated males decreased gradually as the level of irradiation increased and the hatching rate of the 75 Gy treatment group (22.68%±7.20%) was significantly lower than that of the control group (74.38%±6.15%). The average life span of males in irradiation treatment groups was also lower than that of control males. [Conclusion]  Irradiation with low dosage of ⁶⁰Co-γ reduced reproductive parameters of G. molesta. These results provide a guide for further optimization of irradiation conditions and the use of ⁶⁰Co-γ radiation in the management of this pest.