The invention discloses a method for promoting recombinant yarrowia lipolytica bacteria to synthesize phloretin. According to the method, tyrosine is used as a raw material, recombinant yarrowia lipolytica bacteria are used as host bacteria, and the phloretin is obtained through the catalytic reaction of a plurality of enzymes in the host bacteria. According to the invention, the high accumulation amount of acetyl coenzyme A in arrowia lipolytica bacterium cells is utilized, and by introducing a beneficial mutant fragment of a POX2 promoter, driving the acetyl coenzyme A to be converted into a key gene ACC1 of malonyl coenzyme A and carrying out high-efficiency overexpression on a synthetic key gene 4CL of p-hydroxybenzene propionyl coenzyme A, the accumulation amounts of two important precursor substances, i.e., the malonyl coenzyme A and the p-hydroxybenzene propionyl coenzyme A, for synthesizing the phloretin are increased, so that the yield of the phloretin in the host bacteria is finally increased. According to the method, a phloretin anabolic pathway is constructed in microorganisms, large-scale extraction and separation processes are effectively avoided, and the method is environment-friendly and pollution-free and meets the new requirements of current green production.