Abstract: Investigations were carried out on 25-year Robinia pseudoacacia plantations in Culai Mountain, Tai’an, Shandong province. Temporary sample plots were established in stands with different site condition for site quality evaluation. Regression analysis and quantified model I demonstrated that the dominant environmental factors for the growth of R. pseudoacacia were slope aspect, slope gradient and soil thickness. Site quality evaluation model for R. pseudoacacia plantation in Culai Mountain was Y=1.677+0.251X4+0.019X2+0.033X3. R. pseudoacacia plantation in Culai Mountain could be divided into 6 types by the model. Quantification evaluation on site quality indicated that site with score greater than 16.698 was suitable for the growth of R. pseudoacacia.