The results from studying two reproduction methods of wild flat bromegrass show that the seed yield,germination rate(without any treatment) and average total reproduction efficiency of asexual and sexual reproduction method is 270.00 g/m2,80% and 34.24% respectively.The growth speed of flat bromegrass by sexual reproduction is slow(0.361 cm/d) at seedling stage,but the growth speed raises after tillage and the growth speed is up to maximum at flower stage.The survival rate of flat bromegrass by asexual reproduction is up to 89.7% and the growth speed of flat bromegrass by asexual reproduction is quicker than that by sexual reproduction.The growth speed of flat bromegrass by asexual reproduction drops with plant growth and its seed yield increases with biomass increase of the aerial part.