Abstract: The olive tree (Olea europaea L.) is a dioecious plant that produces high-quality edible oil from its fresh fruit flesh. However, it suffers from a low fruit set rate. In this study, we observed the flowering characteristics of olive trees and investigated the effects of pollen and resource limitations on female reproductive success through artificial pollination, supplementary fertilization, different leaf pruning ratios, and different flower thinning ratios. We aimed to explore the reproductive mechanism of the "many flowers, few fruits" phenomenon in this plant. The results showed that each individual olive flower had a blooming period of 3 to 4 days, with complete flowers maturing earlier than male flowers, indicating a tendency to reduce self-pollination and support cross-pollination. The blooming period of a single olive tree lasted for 4 to 5 days, while the peak flowering period of the population lasted for 6 to 9 days, displaying a "mass-flowering pattern". The flowers were fragrant and attracted various insects, which could lead to self-pollination. There was no significant difference in fruit set rate and individual fruit weight among the three treatments: artificial cross-pollination, wind-mediated pollination, and natural pollination. This suggests that the source and quantity of pollen did not affect female reproductive success in olive trees. However, there was a resource limitation for successful female reproduction in olive trees. Supplementary fertilization significantly increased the number of flower clusters per reproductive branch, the number of complete flowers per cluster, fruit set rate, and individual fruit weight. As the leaf pruning ratio increased, the fruit set rate and individual fruit weight significantly decreased. The fruit set rate and individual fruit weight decreased with a leaf pruning ratio of 1/4, but the difference was not significant compared to the control. However, when 2/4, 3/4, or all leaves were pruned, the fruit set rate and individual fruit weight were significantly lower than the control. With an increase in flower thinning ratio, the fruit set rate of initial flowers decreased, while the fruit set rate of retained flowers initially decreased and then increased. The individual fruit weight increased with a flower thinning ratio of 1/4, but as the flower thinning ratio continued to increase, the difference in individual fruit weight compared to the control was not significant. Overall, olive trees have a very low fruit set rate, and various factors may interact to contribute to this low level of fruit set. The hypotheses of male function and resource limitation seem to be reasonable explanations for the "many flowers, few fruits" reproductive strategy in olive trees.