Hemerocallis lilio-asphodelus, a perennial herb of Liliaceae, with brilliant flower color, marked flower shape, ornamental and medicinal value, was used as experiment material. The experiments of quantitative measurement, pollen germination, emasculation, bagging and artificial pollination were conducted to study the flowering character, pollen viability, stigma receptivity and breeding system of H. lilio-asphodelus. The surface pattern of stigma and pollen were observed by an electron microscope as well. The results showed that: H. lilio-asphodelus had large fragrant flowers and the individual flower longevity was about 2 days. Floral character could attract pollinators. The pollen viability gradually increased and reached to the highest at about 12 h to 18 h after flowering, and the stigma had pollen receptivity from the beginning of bloom and lasted the whole flowering period. The stigma exceeded stamen in position. The total value of outcrossing index (OCI ) was 4 and the value of pollens and ovules was about 1 838. The rate of setting fruit reached 82.93% under natural conditions. With artificial self-pollination and cross-pollination, the rate of setting fruit was 96.68% and 94.32%, respectively. The rate of setting fruit with artificial geitonogamy was 83.45%. In conclusion, the breeding system of H. lilio-asphodelus could be determined as facultative outcrossing, self-compatible and pollinators dependent and have no syngamy.