With an experiment conducted Taiping experimental national forestry farm, Yanping districet, Nanping city of Fujian Province, this study was aimed to investigate the effects of nitrogen and phosphorus addition on the conversion rate and the coupling of N-P mineralization in Machilus pauhoi and to provide reference for the selection of reasonable fertilization methods. The study was carried out in Machilus pauhoi plantations with 6 years N and P addition experiment, the cultivation experiment in situ was conducted to determinate the N and P mineralization, that in order to determine the effect of N and P addition on soil N and P mineralization. The results indicated that +N addition treat only significantly increased soil NO₃^--N, but inhibited soil N and P mineralization and β-N- acetylglucosaminidase (NAG). +NP treat significantly increased soil soluble organic N. N and P co-addition (+NP) significantly increased soil soluble organic nitrogen content and N mineralization and P mineralization and acid phosphatase activity. Compared with N addition, N mineralization and P mineralization increasing by 24.25% and 85.95%. However, the effect of +P treat on both N mineralization and P mineralization was not significant (P>0.05). The mixed linear model results indicate that P mineralization was significantly and positively correlated with soil soluble organic N and pH. N mineralization was significantly positively correlated with soil soluble organic N, but was significantly negatively correlated with bulk weight. The results of our study reveaked a quadratic curve coupling of N and P mineralization rates. +NP treat significantly increased the rate of soil N and P mineralization. We found that soil pH, soluble organic N and bulk weight were the main factors