Mixing broad-leaved tree species is an important measure to improve soil fertility and enhance nutrient cycling in coniferous forests, but their mixed effects vary with coniferous tree species. Masson pine (Pinus massoniana) and slash pine (P. elliottii) are widely planted in the subtropical China. However, the mixed effects of the two coniferous forests are still not clear. Soils with 60 cm depth were collected in four forest types:masson pine plantation (MP), slash pine plantation (SP) and two mixed forest of Schima superba with MP (MPM) and SP (SPM), to determine the bulk density, organic carbon (OC), total nitrogen (TN) and total phosphorus (TP) concentrations. The carbon, nitrogen and phosphorus storages and their stoichiometry were also calculated. The OC concentration of MP in 0-60 cm soil layer significantly increased by mixing with broad-leaved tree species, but there was no significant difference in OC concentrations between SP and SPM. Meanwhile, the TN concentrations of MP and SP increased in response to mixed effects. The OC storage of 0-60 cm soil depth in MPM increased by 95.8% compared with MP, while mixing with broad-leaved species had no effect on soil OC storage in SP. The total N storage of 0-60 cm soil depth in MP and SP significantly increased by 15.8% and 28.4% respectively after mixing with broad-leaved tree species. The soil C/N of MP in 0-40 cm soil layer increased and soil C/N of SP in 0-10 cm soil layer decreased after mixing with broad-leaved tree species. The soil C/P in 0-20 cm and soil N/P in 0-10 cm of MP while significantly increased induced by mixed effect, whereas there was only significant difference in soil N/P in 0-10 cm layer between SP and SPM. Soil nitrogen storages increased after the two coniferous forests mixed with broad-leaved tree species, while no significant influence of mixed effects was observed on the phosphorus storage. Moreover, the characteristics of soil carbon, nitrogen and phosphorus stoichiometry were influenced by mixing effects. And, the soil nutrients concentrations, storages and their stoichiometry characteristics of MP were more sensitive to mixed effects compared with those of SP.