The invention provides a method for calculating the blast momentum in a blast furnace production process, wherein the real-time blast momentum in the blast furnace production process is calculated according to the controllable operation parameters of blast furnaces with different converter capacities during the daily production process, and the controllable operation parameters comprise the coefficient, the blast furnace blast volume GFL, the rich oxygen content FYL in the blast, the blast humidity GFSF, the hot air temperature RFWD, the blast pressure GFYL, the working air port number FKGS, the nitrogen density k1, the oxygen density k2, the gravity acceleration k3, the water vapor density, the Kelvin temperature k5 at the temperature of 0 DEG C, and the atmospheric pressure k6 under thestandard state. According to the present invention, with the method, the reasonable blast momentum can be onlinely and real-timely controlled during the blast furnace production, such that the reasonable daily blast furnace production operation is performed from the formation and control angle of the reasonable coal gas flow inside the furnace hearth so as to ensure the long service life of the blast furnace and the low consumption, stability and smooth operation of the production.