The invention discloses a sweet potato fertilizer used in summer and autumn, which comprises the following components according to the mass fraction: 120 to 160 parts of urea, 60 to 80 parts of monoammonium phosphate, 70 to 80 parts of potassium sulfate, 40 to 50 parts of copper sulfate, 60 to 64 parts of magnesium sulfate, 20 to 30 parts of humic acid, 15 to 25 parts of nitro-humic acid, 8 to 14parts of EDTA chelated zinc, 6 to 12 parts of EDTA chelated iron, and 4 to 10 parts of EDTA chelated boron. Compared with the prior art, according to the nutrient absorption ratio of sweet potato, thenutrient distribution ratio is scientific, the component utilization rate is increased, the soil acidification and soil hardening problems can be alleviated, and the agricultural cost is reduced.