Primula filchnerae Knuth is a rare and endangered plant in China. Study on flowering phenology, pollinator and flower visiting behavior, pollen vitality, stigma receptivity, breeding system, and clarify pollination characteristics and endangered mechanism of Primula filchnerae Knuth.Taking the wild population of P. filchnerae in Mianxian as the research object, the pollination biology of P. filchnerae was studied for the first time through field observation and artificial pollination experiments. The results showed that: (1) The flowering period of the P. filchnerae population is from February to mid-April, the single-flowered flowering period is generally for 14 to 17 days. There were 6 obvious developmental changes in the flower morphology during the single flower flowering process, which were all wrapped by sepals, buds extended and showed dark pink, flowers opened and showed pale pink, corolla was white, flowers withered, corolla fell off and calyx persistent. (2) P. filchnerae is an outcrossing plant pollinated by Apis. (3) The stigma was receptive before the anthers dehiscence, the receptivity gradually increased, the anthers began to dehiscence and loose pollen on the third day after the petals opened, the vitality was the highest on the fourth day at 98.18%, then gradually weakened. (4) A study of the breeding system indicated that the pollen-ovule ratio of the long-styled and the short-styled were 902.26 and 831.48 respectively, the hybridization index (OCI) was 4, bagging experiment show that the heterozygous mating is fertile and homozygous mating is not fertile. This shows that the breeding system of P. filchnerae is outcrossing and self-incompatible, it needs pollinators. In conclusion, few pollinators, self-incompatible, ovule abortion may be the important reasons for the endangerment of P. filchnerae.