The invention discloses a 40% weaned piglet concentrate feed. Components comprise dehulled soybean meal, zymolytic plant small peptide, fish meal, choline chloride, acidifying agents, flavoring agent, tasty agents, suckling pig composite vitamin, suckling pig composite organic microelements, lysine, methionine, probiotics (lactic acid bacteria, saccharomycetes and brevibacterium bacteria), calcium hydrophosphate, vegetable oil and mountain flour. The feed is convenient to use; and corn flour is added and mixed evenly according to a recommended formula, so that a nursery pig complete formula feed can be prepared, nutrient requirements of nursery pigs are met completely, piglet growth potentials can be fully displayed, and economic benefits are improved. According to the feed, a low dosage of antibiotics which are dedicated for animals and cannot be absorbed is used, food safety is guaranteed, and the feed utilizes organic microelements with high bioavailability and does not contain high calcium, phosphorus, copper and zinc, so that the feed is environment friendly.