Abstract: In order to improve the structure of low-efficiency forest in hilly,the total carbon（C）release of Pinus massoniana and native broad-leaved tree species in the process of mixed decomposition of litter was investigated. The litters of Pinus massoniana,Sassafras tzumu,Cinnamomum camphora and Toona sinensis that widely distributed in South China were divided into 35 treatments according to different tree species combination and mixed proportion,and then field decomposition experiments were carried out to explore the best combination and mixing ratio of C release. The results showed that the C release of leaf litter of T. sinensis was the fastest,followed by S. tzumu and C. camphora litter,and the slowest in P. massoniana litter among the four tree species,In 31 mixed litter leaves treatments,the non-additive effect of C release increased at first and then decreased with the extension of decomposition time. Compared with other seasons,the non-additive effect of C release rate decreased in autumn. Among the combinations of P. massoniana with a broad tree,the synergistic effect of PC73 and PC64 was stronger in the treatment with broadleaf accounting for more than 30%in the combination of P. massoniana and C. camphora leaf litter;Among the combination of P. massoniana with two or three broad trees,the treatment with broad leaf accounting for more than 30% and containing T. sinensis litter:PST613 and 712,PCT631 and 613,PSCT7111 and 6121 showed stronger synergistic effect.