Currently in Vietnam, Pleurotus citrinopileatus is grown on cellulose-rich substrates. Pleurotus citrinopileatus was grown on a substrate of rubber sawdust and waste substrate after growing Ganoderma lucidum. The cultivation of Pleurotus citrinopileatus mushroom on the waste substrate after growing Ganoderma lucidum is to take advantage of agricultural waste and to create edible mushroom products for the market. These substrates were rich in cellulose and were supplemented with cow manure at different ratios of 0%, 2%, 4%, 6%, and 8% to obtain the average weight of fresh fruit bodies per plant embryo bag and biological efficiency B.E (%). This study is for surveying the effect of cow manure rate on the average weight of fresh fruit, B.E (%) of Pleurotus citrinopileatus on two substrates, including rubber sawdust and waste residue, after growing Ganoderma lucidum.