The invention relates to a synthesis method of 6,7-substituted-4-aniline quinazoline. In the method, substances such as 3,4-substituted benzoic acid, and the like are used as starting materials, and the 6,7-substituted-4-aniline quinazoline is prepared through a reaction path of esterification reaction, oxygen-alkylation reaction, nitration reaction, nitro reduction reaction, ring closing reaction and two-in-one reaction or a reaction path of esterification reaction, oxygen-alkylation reaction or nitration reaction, hydrolysis-demethylation reaction after the nitration reaction, esterification reaction, oxygen-alkylation reaction, nitro reduction reaction, ring closing reaction, two-in-one reaction, and the like. The invention also provides a preparation method of a 4-aniline quinazoline derivative with lower starting material cost and higher productivity, which can effectively reduce the production cost so as to improve the competitiveness of a 4-aniline quinazoline derivative product.