The invention discloses a method for promoting cultivation of early-spring cauliflower by using a full-biodegradable film. The method comprises the following steps: 1.1, variety selection; 1.2, sowing is selected from the last ten days of September to the last ten days of December; 1.3, seedling raising; 1.4, soil preparation and fertilization; 1.5, bedding, film covering, transplanting and field planting; 1.6, field management; 1.7, binding leaves and protecting flowers; 1.8, disease and pest control; 1.9, timely harvesting: in the step 1.5, 1-2 days before field planting of the cauliflower, a white or black full-biodegradable film with the width of 1 m and the thickness of 6-10 microns is selected to cover the furrow surface. According to the method, the full-biodegradable film is utilized in cultivation of the cauliflower, temperature increasing and soil moisture conservation can be achieved in the early period of cultivation of the cauliflower, normal growth and yield of the cauliflower are not affected, natural decomposition can be achieved in the later period of growth of the cauliflower, pollution to soil is reduced, the working process of manual film mulching and uncovering can be reduced, and the yield of the cauliflower is increased. And the cost of manual film covering and uncovering treatment is reduced.