The invention relates to a soy milk heating method which comprises the following steps of: a. placing soy milk in a heating container and heating the soy milk with a heater, wherein the heating container is a sealed container during the heating and comprises a barrel body and a head of a soy milk grinder, the head is buckled on the barrel body, and a sealing ring is arranged between the barrel body and the head and seals the space between barrel body and the head; b. heating the soy milk with the heater, forming a pressure higher than the atmospheric pressure by 21-30 KPA in the heating container under the action of the head weight and the sealing ring, and boiling the soy milk; and c. continuously heating by keeping the temperature at a range of 100-105 DEG C, till the soy milk is cooked. In the invention, the soy milk is boiled by forming the pressure higher than the atmospheric pressure by 21-30 KPA in the heating container; and when a higher pressure exists in the heating container, the boiling point of the soy milk can be improved so as to prevent the boiling soy milk from flowing out of a pot. The soy milk heating method realizes fast soy milk making and better mouth taste of the soy milk and saves more time and electricity.