The invention relates to the technical field of preparation of organic photoelectric materials, in particular to a preparation method of 1, 3-dimethyl-1, 2, 3, 4-
cyclobutane tetracarboxylic dianhydride. The preparation method comprises the following steps: (1) carrying out
addition reaction on
dimethyl carbonate, a catalyst and dimethyl citraconate under the
irradiation of a mercury lamp source to obtain an intermediate S1; (2) adding the intermediate S1 into an acidic solution, heating and carrying out
hydrolysis reaction to obtain an intermediate S2; and (3) adding the intermediate S2 into
acetic anhydride, heating and stirring, and carrying out
dehydration ring closing reaction to obtain the finished product 1, 3-DMCBDA. According to the method, the defects in the prior art are overcome, the purity of the produced 1, 3-dimethyl-1, 2, 3, 4-
cyclobutane tetracarboxylic dianhydride is improved, and the content of isomers and the content of
metal impurities are greatly reduced.