Analysis and assessment of the influence of different forest types on soil nutrients are of great significant to reveal the relationships between forests and soil nutrients, and to comprehensively evaluate soil fertility in forests. In this study, characteristics of soil nutrient states were investigated in six forest types (Cunninghamia lanceolata pure forest, Schima superb pure forest, S.superba+Phoebe ahenre mixed forest, S.superba+C.lanceolata mixed forest, Cyclobalanopsis glauca natural secondary forest, and Phyllostachys edulis forest) in central subtropical areas of China, by using the structural equation model. The results showed that: (1) the soil organic matter (SOM), total nitrogen (TN), available nitrogen (AN) and available phosphorus (AP) in soil (0-60 cm) ranged 8.24-28.17 g/kg, 0.67-1.31 g/kg, 44.88-89.31 mg/kg, and 1.24-6.50 mg/kg, respectively, in the examined forests. The highest values of these nutrients were found in the C.glauca natural secondary forests. The lowest contents of SOM and AN occurred in the P.edulis forests. The lowest contents of soil TN and AP were found in both C.lanceolatapure forests and S.superba pure forests. The contents of total phosphorus (TP) and available potassium (AK) in soil (0-60 cm) ranged 0.15-0.21 g/kg and 35.54-54.32 mg/kg, respectively, in the six forest types, with the highest contents in S.superba+P.ahenre mixed forests, and the lowest contents in S.superb pure forests and P.edulis forests. (2) The SOM, TN, TP and AP contents gradually decreased with increasing of soil depth in the six forest types, but no vertical changing patterns of AN and AK were found in the examined forests. (3) The comprehensive score of soil nutrients was 3.47 in C.glauca natural secondary forests, which belonged to the upper middle level of soil fertility. The comprehensive scores of soil nutrients were 2.45, 2.76, 2.83 and 2.68 in C.lanceolata pure forests, S.superba pure forests, S.superba+P.ahenre mixed forests, and S.superba+C.lanceolata mixed forests, respectively, which all belonged to the lower middle level of soil fertility. The P.edulis forests had the lowest score of soil nutrients (1.95), indicating that the forest type was in a soil nutrient deficient status in the study region.The results demonstrated that the natural forests are beneficial to maintain soil nutrients and to reduce soil erosion compared to artificial forest plantations.The structural equation model further indicated that the soil organic matter was the most important factor in affecting soil fertility in the six forest types in the studied area.