Abstract: For investigating the content of main nutrients in mushroom residues from corn cob, and utilizing mixed mushroom residues in the cultivation of Pleurotus ostreatus.The main nutrients of 2 kinds of mushroom residues from corn cob were determined by kjeldahl method, phenol-sulfate method and soxhlet extraction method.The results showed that the content of polysaccharide, total protein and crude fat were increased significantly, but the crude fiber content decreased obviously in mushroom residues after the Lentinus edodes and Schizophyllum commune were cultivated by corn cob. The content of polysaccharides and crude fat in the residues of S. commune were reached to 0.63% and 1.24% respectively, while the content of total protein in the residues of Lentinus edodes was higher, reaching up to 7.46%. P. oostreatus was cultivated by the mixed mushroom residues of L. edodes and S. commune. Results demonstrated that P. ostreatus was able to grow and fruiting normally, and the mycelium morphology, growth rate and biological conversion rate of fruiting bodies were affected by different substrate ratios. The formula B (40% mixed mushroom residues + 50% mixed wood chips) was the optimal substrate for the cultivation of P. ostreatus, which showed the good mycelium shape and high yield. The biological conversion rate was up to 70.69%. The secondly was the formula E (90% mixed wood chips), and the biological conversion rate was 70.03%. The third was formula D (90% mushroom residues of corn cob), the biological conversion rate was 56.54%.The formula F (90% corn cob) was the worst, with biological conversion rate just 52.4%.