The invention provides a black soybean cake processing method. The processing comprises the steps that 1, black soybean powder, glutinous rice flour, rice flour, red dates, lily, sweet-scented osmanthus, the fruits of Chinese wolfberry, mint leaves, granulated sugar, sesame powder and palm oil are weighed; 2, the red dates, the lily, the sweet-scented osmanthus, the fruits of Chinese wolfberry and the mint leaves are heated and decocted; 3, the granulated sugar is heated to be dissolved; 4, the black soybean powder, the glutinous rice flour and the rice flour are mixed, and then mixed liquid and the palm oil are added in the mixture for high-temperature steaming; 5, the steamed cake is coated with the sesame powder in a rolling mode. The black soybean cake processing method has simple steps, the black soybean cake is crisp and delicious and makes people enjoy aftertaste, and black soybeans have rich nutrients and have the effects of promoting cholesterol metabolism, lowering blood lipid, preventing cardiovascular disease and the like. Meanwhile, due to the fact that the red dates, the lily, the sweet-scented osmanthus, the fruits of Chinese wolfberry, the mint leaves and the like are added in the formula, the black soybean cake has the effects of enriching yin, nourishing kidney, protecting the liver, nourishing the stomach, discharging toxicant, keeping beauty and the like.