Considering the importance of the allowable pollutant total control quota in water resources protection and the seasonal variation of water environmental carrying capacity, and with referencing the determination of river two-dimensional model parameters, a calculation method on pollution carrying capacity is explored by using this model. With an eye to the environmental protection and the differences of environmental carrying capacity among water functional areas, a suggestion that selecting a function area of the minimum bearing capacity is regarded as to be the allowable pollutant total control quota is proposed. Such analysis calculation method of water environmental carrying capacity and allowable pollutant total control quota can provide basis for water pollution control of rivers in Baoji City.