The biomass and energy allocation among the rhizome, vegetative shoot, reproductive shoot and population modulus of Leymus chinensis were studied by using modulus analysis. The results show that there was not trade-off between vegetative shoot biomass/energy and reproductive shoot bimass/energy, but there was trade-off between rhizome biomass/energy and vegetative shoot biomass/energy. The results also show that there was not significant different between the rate of biomass allocation and the rate of e...