Abstract: The biomass, energy and nutrient (N, P, K) contents of different components (stems, leaves, flowers, pods) were measured at different phenological stages (budding, flowering, podding, and maturity stages) of Glycyrrhiza inflata in the extremely arid climate in Xinjiang to explore the dynamic changes of reproductive allocation in biomass, energy and nutrients in the phenological stages. 1) The reproductive allocation of G. inflata increased with the phenological stage. In budding, flowering, podding and maturity stages, reproductive allocation was 2.40%, 4.30%, 13.90%, and 18.90%, respectively. 2) The phenotype plasticity of the reproductive module was higher than that of the vegetative module, and sexual reproduction decreased with progressive phenological stages. 3) Biomass of flowers (pods) had significant (P<0.05), positive and linear correlations with the leaf biomass, stem biomass or total biomass in the four phenological stages. 4) The energy and nutrient element allocation of different modules varied consistently with the biomass: the highest values in leaves were in the flowering stage, in stems were in the budding stage, and they increased with the phenological stages in reproductive modules. In conclusion, the sexual reproduction of G. inflate was an accumulative process of matter, energy, and nutrient elements, with a minor proportion used for sexual reproduction but the majority used for vegetative growth.