Abstract:The geographic distribution of Pinus tabulaeformis is discribed on the basis of exploration in 1978-1979 and the provenance regions is classified by means of principal component analysis.The horizontal distribution of this Pine covers a wide range with quite different climatic conditions and is characteristic of discontinuity due to arid and human disturbances. It extends over several vegetation zones (desert, steppe, deciduous broad leaved-forest and north subtropical forest). The vertical distribution in east is 100-1500m, in Yanshan region and rises to 2000-2700m. in west in Qinghai province,but from south to north the upper limits vary little in general, even though lower limits evidently rise through the same direction. The correlation coefficient of upper limits with latitude is -0.43, but not significant, with longitude is -0.71**, significant; The correlation coefficient of lower limits with latitude is 0.55**, with longitude -0.84**, both significant.In the principal component analysis, derived from the correlation matrix computed on eight climatic and geographic variables (annual mean temperature, January mean temperature, July mean temperature, thermo-index, annual precipitation, aridity in spring, latitude, longitude), the eigenvalues and eigenvectors are computed. Because λ1 and λ2, account for 86.8% of total variance, using first and second principal component scors, the two dimension‘s ordination diagram is constructed, denoting the similarity in climate conditions of some forest region. According to this, the entire range of Pinus tabulaeformis is divided into ten provenance regions.