According to the data of solar direct radiation observation at the Yunling Bai-mang Snow Mountain in the cenT_Ral part of the Hengduan Mountain Range in 1983 and 1984,the Linke atmosphere turbidity coefficient T_P was calculated and analysed. It's found that T_P decreases with the increase of altitude. The annual variations of T_P show similar T_Rend at different altitude.T_P is maximum in July and August, and T_P is Minimum in November. T_P may he divided into the aerosol turbidity coefficient T_R and the vapour turbidity coefficient T_W, The annual variation of T_W is in accordance with the annual disT_Ribution of the precipitation, and T_R shows the opposite variation tendency.