The invention discloses a synthetic method of polyether-isotridecanol monoester, and the method comprises the following steps: adding isotridecanol, carboxylic binary acid monomers, a dehydrating agent and a catalyst into a reaction container for carrying out esterification, and obtaining ester; further cooling the ester to below 45 DEG C; adding polyether into the cooled ester, adding the dehydrating agent and the catalyst, then heating up, refluxing, and gradually heating up to 120-190 DEG C; keeping the temperature for 1-2h, and measuring the acid value during the temperature-keeping reaction process till the carboxyl reaction is complete; and cooling to below 45 DEG C, and obtaining the polyether-isotridecanol monoester, wherein the molar ratio of isotridecanol: carboxylic binary acidmonomers: polyether is 1-1.05:1:1-1.05. The synthetic method has the advantages of few steps, simple operation, easy realization of industrial production, low equipment investment, economy and feasibility; as the composite catalyst is adopted, the yield of the polyether-isotridecanol monoester is increased to above 90% from the original 60%.