A synthesis method for the raw material drug phloroglucinol was provided by using 2,6-dichlorophenol as the starting material and high boiling point solvent 1,2,4-trimethylbenzene as the dispersant.Under the catalysis of cuprous chloride,it reacts with potassium hydroxide under atmospheric pressure and heat stirring to eliminate the reaction.At the end of the reaction,purified water was added for static stratification,and the upper solvent was separated,the pH value of the lower aqueous phase with concentrated hydrochloric acid was adjusted to 2.0 until crystals precipitate,filter and dry the crude product of phloroglucinol,and recrystallize the aqueous phase to obtain a white like product of phloroglucinol.The yield of the entire process is over 70%,and the purity is as high as 99.83%.The synthesis process route is simple,and the post-treatment is convenient and easy to operate,making it suitable for industrial production.