The invention relates to a dibenzyl-macrolide compound based on photoreaction and a synthesis method thereof. The synthesis method comprises the following steps: dissolving dibenzyl-ortho-dicarbonyl compounds and olefins in anhydrous benzene or anhydrous acetonitrile, and reacting under the illumination of 400-760nm continuous light; monitoring the reaction process by TLC (thin layer chromatography); after the all dibenzyl-ortho-dicarbonyl compounds are converted into the intermediate product 2,3-dihydro-1,4-dioxin compounds, evaporating to remove the benzene under reduced pressure; dissolving by adding anhydrous acetonitrile, wherein if the previous solvent is acetonitrile, the step can be omitted; while introducing oxygen, illuminating the solution with continuous light of which the wavelength is 400-760nm or 300-760nm; and monitoring the reaction process by TLC, carrying out column chromatography after the reaction finishes, thereby obtaining the dibenzyl-macrolide compound. The method is simple to operate, the atom utilization ratio is up to 100%, and the raw materials are cheap and have high synthesis value.