The invention belongs to the technical field of animal nutrition and feed formulas, and particularly relates to antibiotics-free fermented feed for Hainan black pigs and a method for preparing the antibiotics-free fermented feed. The antibiotics-free fermented feed for the Hainan black pigs comprises, by weight, 35-73% of corn, 4-25% of bean pulp, 0.5-6% of fish meal, 4-20% of rice bran meal, 5-15% of coconut meal, 4-12% of bran, 0.5-1.6% of stone powder, 0.8-1.5% of calcium hydrogen phosphate, 0.2-0.5% of table salt, 0.1-1.0% of premixes and 0.01-0.5% of enzyme preparations. The method for preparing the antibiotics-free fermented feed for the Hainan black pigs includes smashing and treating the corn, the bean pulp, the fish meal, the rice bran meal, the coconut meal, the bran, the stone powder and the like; matching the corn, the bean pulp, the fish meal, the rice bran meal, the coconut meal, the bran, the stone powder and the like with the calcium hydrogen phosphate, the table salt, the premixes and the enzyme preparations to obtain basic fermentation substrates; adding complex microbial preparations into the basic fermentation substrates and carrying out sufficient fermentation treatment to obtain the antibiotics-free fermented feed with comprehensive and balanced nutrition. The antibiotics-free fermented feed and the method have the advantages that 4-50% of antibiotics-free fermented feed is added into conventional compound feed for black pigs at different phases, accordingly, the breeding costs of the Hainan black pig can be reduced, the feed intake and the growth speeds can be increased, the health of gastrointestinal tracts of sow and piglets can be improved, and the productivity of the Hainan black pigs can be enhanced.