Abstruct: Moso bamboo(Phyllostachys edulis) has advanced rhizome-root system and strong expansion ability. To study the variation of soil nutrients and their stoichiometric characteristics in different expansion stages of moso bamboo to Cunninghamia lanceolata can provide basis for rational regulation and ecological management of moso bamboo pubescens forest. In this study, taking the interface of moso bamboo-chinese fir forest as the research object, contents and correlations of soil organic carbon, total nitrogen, total phosphorus, alkali-hydrolyzed nitrogen and available phosphorus at different expansive stages were compared and analyzed to reveal the effects of moso bamboo expansions on soil nutrients and stoichiometric characteristics. The study shows: (1 ) Moso bamboo to Cunninghamia lanceolata, with the increase of moso bamboo proportion, the content of soil organic carbon (C) increased first and then decreased, and the coefficient of variation of soil organic carbon increased gradually with the deepening of soil layer; the content of total nitrogen (N) increased first and then decreased, and the difference of total nitrogen content in 10-20 cm soil layer reached a significant level in the finalr stage of expansion than in the initial stage of expansion; The content of total phosphorus (P), hydrolyzed nitrogen (H-N) and available phosphorus (A-P) showed a wave-like change trend with the expansion of moso bamboo. The content of total phosphorus, hydrolyzed nitrogen and available phosphorus in different expansion stages reached significant levels. The content of total phosphorus and available phosphorus in final expansion stage was lower than that in initial expansion stage, and the content of alkali hydrolyzed nitrogen was higher than that in initial expansion stage. (2) During the expansion of moso bamboo to Cunninghamia lanceolata, C:N showed an upward trend with the expansion of Moso bamboo, and the difference between different expansion stages reached a significant level; N:P showed an upward trend with the expansion of Moso bamboo. The difference of N:P in 0-20 cm soil layers reached a significant level, while that in 20-30 cm soil did not reach a significant level. H-N:A-P increased first and then decreased with the expansion of Moso bamboo, and the difference between different expansion stages reached a significant level, and the finalr expansion stage was smaller than the initial expansion stage. (3) C, N, P and C: N, N: P, HN: AP are significantly correfinald, and the correlation coefficient reaches a significant level. Among them, C and N are negatively correfinald with H-N:A-P, P is negatively correfinald with N:P and H-N:A-P. In summary, the proportion of moso bamboo increased gradually during the expansion of moso bamboo to Cunninghamia lanceolata, changing the community structure of the expansion interface, changing the preference of vegetation for soil nutrient utilization, increasing the content of C, N and A-P in soil, and reducing the content of P and H-N in soil. C:N and N:P increased with the increase of the proportion of bamboo, but N:P was lower than the average level of soil in China and C:N was higher than the average level of soil in China. This reflects that with the expansion of bamboo, soil N and P elements were more scarce. It is suggested that N and P elements be supplemented in time to promote the stable and healthy development of community.