Abstract: This paper is a continued work of the similar research conducted by the senior author et al in 1978—1979.The area covered by this research has been expanded to the whole western mountain area in Beijing.66 new sample plots were set up in various site conditions,in which besides all the ordinary measurements 4 additional growth parameters (top heights Ⅰ and Ⅱ,growth intercepts Ⅰ and Ⅱ) were measured.After statistical processing of the data with the emphasis on the multiple regression analysis of the growth parameters in connection with their site factors,it has been found out that the soil fertility is the dominant factor and the elevation and aspect are the subdominant factor that influnce the growth of Pinus tabulaeformis.Some multiple regression equations have been worked out,according to which the growth prediction tables for the top heights and growing stocks of Pinus tabulaeformis at the standard age of 25 have been made.The most suitable sites,normally suitable site and unsuitable site for Pinustabulae-formis have been distinguished.