The invention belongs to the technical field of synthetic perfumes, and specifically relates to a continuous synthesis method of milk lactone perfume. The continuous synthesis method comprises the following steps: carrying out aldol reaction under the action of alkaline water, then carrying out hydrogenation reaction and Baeyer-Villiger oxidation, carrying out acidic continuous hydrolysis, and dehydrating the product to obtain the milk lactone perfume, wherein the aldol reaction comprises: uniformly mixing part of cyclohexanone serving as a base material with the alkaline water, heating the mixture, dropwise adding a mixture of the remaining cyclohexanone and n-butyraldehyde, stirring the materials while the mixture is dropwise added, continuously stirring after the dropwise adding is ended, and ending the heat-preserved reaction till the content of the n-butyraldehyde is less than 1 percent; allowing the solution to stand still, separating an oil layer, collecting a water layer for recycling and use; washing the collected oil layer with water, then transferring the oil layer into a distillation still for distillation to recycle excessive cyclohexanone for use; collecting a condensation product at the bottom of the distillation still. According to the continuous synthesis method, the yield of the aldol reaction is increased by adding the cyclohexanone in different ways; furthermore, under a reaction temperature condition of the continuous synthesis method, an aldol condensation product can be obtained in one step.