Abstract: In this paper, the method of variance/mean ratio and χ² test by 2×2 contingency table are used to study the pattern and associations between dominants of the vegetation in Mian Mountain, Shanxi Province. The results indicated that the pattern of dominants follows contagious distribution, that the positive association between species is due to the same suitability of species for homogeneous habitat, that the negetive association is due to the different adaptabitity of different species for heterogeneous habitat. Besides, χ² test is used to study association between species, association intensity between species is measured by point correlation coefficient. It is necessary that point correlation coefficient is calculated as supplementary interpretation to association between species. By analysising association between species, dynamic succession tendency of the vegetation in Mian Mountain may be seen.