The interaction between pollinating fig wasps (Agaonidae) and their host fig trees (Ficus) is a striking example of obligate pollination mutualism. Ficus and its pollinating fig wasps rely on each other, and the coevolutionary relationship may date back to 75 Myr. Very rarely, the pollinating fig wasp evolves cheating in the fig-fig wasp mutualism, in which the pollinator loses pollination ability but still lays eggs in female flowers. Ficus altissima is a monoecious fig species in which seeds and wasps are produced in the same figs. The figs of F. altissima are occupied by two Eupristina species in the Xishuangbanna region: the pollinating fig wasp Eupristina altissima and the cheater Eupristina sp.. The two species share similar biological characteristics but have different reproductive strategies. In this study, we compared the reproductive differences between the two wasp species during emergence, oviposition, and pollination. The results for both species showed that newly emerging females were small on average, but some smaller females died during dispersal so that larger females arrived at receptive trees. When entering the figs, however, some larger pollinators were trapped in the ostiole so that the pollinators arriving in the fig cavity were smaller. The cheater, in contrast, easily passed through the ostiole so that the females arriving in the fig cavity were large. This suggests that the two species have different abilities to pass through the ostiole. In both E. altissima and Eupristina sp. females, larger wasps carried more eggs before oviposition, and there was no significant difference in average egg loads between the two species. When only one female was introduced into a fig, there were enough female flower resources for oviposition and pollination. However, E. altissima and Eupristina sp. did not lay all their eggs so some remained in the ovaries. The numbers of eggs in their ovaries were significantly reduced after oviposition, but the number of eggs remaining did not differ between the two species. Only some pollinating fig wasps used all the pollen grains they carried for pollination, and the wasps that pollinated more successfully, also laid more eggs. The pollinator performed pollination more quickly than oviposition. When two females of the same species were introduced to a fig, the numbers of eggs that both wasp species laid decreased, and the pollination efficiency of the pollinator was also reduced as a result of the intraspecific competition. When one pollinator and one cheater were introduced, the cheater laid eggs more successfully than the pollinator and both pollination and oviposition of the pollinator were restricted as a result of the interspecific competition. These results imply that the pollinating fig wasps only utilized part of the female resources for pollination and oviposition and that the efficiency of pollination was higher than that of oviposition. This could be a mechanism maintaining the fig-fig wasp mutualism. However, the cheater was a stronger competitor when it coexisted in the same figs with the pollinator, and significantly influenced seed and pollinator production. Therefore, for the cheater to stably coexist in the fig-fig wasp mutualism, it needs to reduce direct competition with the pollinator. A good reproductive strategy would be that the pollinator and cheater reproduce separately in different figs, or even in different trees.