Abstract:We investigated the reproductive ecology of Chirita gueilinensis in different habitats populations (YZ population,semi-wild,at the sunny cracks and crevices of calcareous rocks with little soil; DB population,at the rupicolous in a cave). Our results indicated that: (1)Flowering took place from late February to middle April,and anthesis of a single flower lasted 10~17 days in YZ population and 16~24 days in DB population depending on environmental conditions. (2)The pollen-ovule ratio(P/O) is different in the two populations,and we noted larger variation in pollen than ovule production,which may be related to habitats. (3)Breeding experiments showed that C. gueilinensis is facultative xenogamy by insects and no agamospermy. (4)There were limitations both in pollination and ripening of seeds,which resulted in a low seed-setting ratio(<45%) for all artificial treatments and natural pollination. (5)Chalcididae sp.and Amegilla albigena(Lepeletier) （DB population） or Apis cerana Fabricius (YZ population) were main pollinators of C. gueilinensis. (6)The reproductive investment per plant increased but the reproductive allocation decreased with increased individual size. （7）Plants in YZ population obtained more available resources from environment and greater reproductive investment than plants in DB population,this indicated that reproductive investment was relatively favored by plants from YZ population, whereas vegetative propagation was favored by plants from DB population to obtain more resources from the environment.