Abstract: In this paper, b y means of Principal Component Analysis (PCA)and Reciprocal Averaging (RA),3 natural secondary forest types were classified at Sankuaishi forestry farm of sin Bin county in Liaoning province. Ⅰ. Quercus mongolica forest type Ⅱ. Juglans mandshurica-Fraxinus mandshurica forest type Ⅲ. Broad-leaf mixed forest type. The ordination of types significantly were influenced by altitude, aspect.According to Fishes test discriminant analysis, the classificants were recognized as justified. Using discriminat eqation: Y=0.0383X1+0.0362X2 +0.0944X3+0.0133X4+0.1191X5-0.051X6 can be predicted natural secondary forest types.