Abstract: Kochia prostrata is subshrub of Chenopodiaceae and fine pasture inhabiting arid zone. Flowering phenology,flowering dynamic,pollen viability and stigma receptivity of K. prostrata were studied. For spicate inflorescence of K. prostrata middle flowers bloomed first,then lower flowers,the upper flowers bloomed at last. For a poly-capitulum,central florets bloomed earlier than bilateral ones. The flowering course of single flower of this species can be divided into female subage and male subage. The female subage can lasted 10 to 12 days and the male subage was 1 day. This species produces two types stigmas and anthers in colour (red and yellow).There are four combination types of stigma and anther in the K. prostrata population. The pollen viability of K. prostrata was highest at initial stage (>80%),higher on the 4 to 8 hours after flowering,and then reduced evidently. The pollen viability of yellow-anthers are longer than the red-stigmas. The change tendency of receptivity of the two colour stigmas is similar. The stigma receptivity appeared on the first day of stigma showing from tepals,and then enhanced with the growth of stigma. The stigma receptivity were highest on the 8 to 12 days after flowering. The period of stigma receptivity was about 12 days,account for 92.3% of single flower blooming. The pollen-ovule ratio (P/O) of K. prostrata was 61900-64200. Based on Cruden’s criterion,the breeding system would be outcross. Floral dynamics,pollen viability and stigma receptivity have significant value to understanding the evolution of breeding system and the ecological adaptive mechanism.