The present study was to investigate the effect of the combined treatment of MeJA and antagonistic yeast Pichia membranifaciens for control of green mold decay caused by Penicillium citrinum on Chinese bayberry fruit(Myrica rubra Seib & Zucc.Cv Wumei) and to analyze the effect of MeJA on the growth of the yeast and pathogen as well as the disease resistance.The results exhibited that the biocontrol activity of P.membranifaciens on the disease was enhanced by the addition of MeJA,1×109 CFU/mL P.membranifaciens combined with 10 μmol/L MeJA resulted in a remarkably improved control of the disease compared with applying yeast or MeJA alone.Meanwhile,the combined treatment induced higher defense-related enzymes activities than either alone.In addition,adding MeJA positively influenced the population of P.membranifaciens in NYDB medium and fruit wounds.However,MeJA had no direct inhibitory effect on spore germination and germ tube elongation of P.citrinum.Thus,these results suggested that MeJA could improve the biocontrol activity of P.membranefaciens on green mold decay on Chinese bayberry fruit and the improved control of the disease by MeJA is directly because of the increased population size of antagonist,and indirectly because of the enhanced disease resistance.