Based on the analysis of land resources and current population status and the characteristics in the Qinghai Lake region, the ultimate and maximal population carrying capacity of land and the pop ulation carrying capacity of cultivated land and grassland and its proportion in each county are estimated. Results show that the ultimate population carrying capacity of land in the region is 695973, in which cultivated land is 483720, grassland is 212703, and the corresponding capacity ratios are 69.44 % and 30.56 %, respectively. The total maximal population carrying capacity of land is 324620, in which cultivated land is 181219, grassland is 143410, and the capacity ratios are 55.82 % and 44.18 %, respectively. The maximal population carrying capacity is diffident in each county. Population carrying capacities of Gonghe County, Haiyan County, Gangcha County, and Tianjun County are 7.01756, 6. 00874, 5.96404, and 0.03318, respectively. The capacity of cultivated land and grassland in each county is also different.