The invention relates to a top pressure increasing baking method of a blast furnace. The top pressure increasing baking method comprises a cold air passing phase, a three-grade heating and temperature keeping phase and a final cooling phase in sequence; when the third-time temperature keep is performed, the top pressure of the blast furnace is increased by 10 kpa every a certain time, and is finally not higher than 70 kpa; and the waste gas humidity of the blast furnace is equal to the atmospheric humidity, and the central temperature of first and second layers of supercompact clay bricks of the blast furnace is not lower than 90 DEG C, the third-time temperature keeping is stopped. The top pressure increasing baking method of the blast furnace can slowly and stably heat up the temperature in the furnace, enables the moisture to be slowly evaporated, prevents the rupture and pulverization of refractory brick layers caused by quick dehydration, and prolongs the service life of the blast furnace; and the method controls the top pressure of the furnace body to be slowly heated up in the baking process, can urge the moisture to be condensed to water drops to slip along the inner wall of the blast furnace and to be drained from a drain hole in the furnace bottom, and can quicken the discharge of the moisture.