The heterostylous plants have been hypothesized to promote compatible pollination between floral morphs within species. To test how the distylous Luculia pinceana promotes compatible pollination and identify the pollinator species, the number of long-styled morph (L-morph) and short-styled morph (S-morph) in the natural populations was counted. Floral traits of the two morphs were measured. The number of intermorph and intramorph pollen grains on the stigmas of the natural populations was counted. The germination rate and pollen tube length between intramorph and intermorph pollination treatments were compared. Several artificial pollination treatments were conducted to test whether L. pinceana was self-incompatible. The visiting insects were observed and the body traits of effective pollinator were measured. The results showed that:(1) there was no significant difference in the plant number of L-morph and S-morph in natural populations. The tube depth, tube diameter, opening diameter, stamen length, and stigma length of L-morph were significantly lower than those of S-morph, while the leaf length, leaf width, pistil length, anther volume, pollen grain volume and stigma thickness of L-morph were significantly higher than those of S-morph. (2) The proportion of intermorph pollen grains on the stigmas of the natural population was significantly lower than that of intramorph pollen grains. (3) The pollen germination rate and pollen tube length of intermorph pollination were significantly larger than those of intramorph and the mix pollination. (4) The seed set of the intermorph pollination treatment was significantly higher than that of intramorph pollination treatment, and intramorph pollination treatment could produce some seeds. (5) The nocturnal and long-tongued hawkmoth (Cechenena Lineosa) was an effective pollinator and its tongue was fit to floral tube of L. pinceana. Our research indicated that distylous L. pinceana promoted compatible pollination by facilitating intermorph pollen germination and pollen tube extending, and was pollinated by the long-tongued hawkmoth which was mechanical fit with its floral traits.