The reproductive success of flowering plants is strongly influenced by pollination mode, particularly in species exhibiting mixed mating systems. This study examined the effects of different pollination treatments on fruit set and seed production in Nigella damascena (Ranunculaceae) under field conditions over two consecutive growing seasons. Flowers were subjected to spontaneous self-pollination, induced self-pollination, geitonogamy, open pollination, induced cross-pollination, and supplemental cross-pollination. Pollination treatment significantly affected both fruit set and seed production, while year had no significant effect on either trait. N. damascena is capable of setting fruit and producing seeds via self-pollination; however, cross-pollination substantially increased both fruit set and seed number per follicular capsule. Notably, self-pollination treatments resulted in an approximately 47-57% reduction in seed set compared to cross-pollination. Although open pollination resulted in high fruit set, supplemental cross-pollination further increased seed number per follicular capsule, indicating pollen limitation of seed production rather than fruit initiation. These findings support a mixed mating system in N. damascena, in which partial self-compatibility provides reproductive assurance, while insect-mediated cross-pollination is essential for optimizing the pollen transition to maximize overall reproductive output.