The invention relates to the synthesis method of an organic compound, in particular to a preparation method of methyl anthranilate. The preparation method comprises the following steps: firstly using phthalic anhydride and ammonia water as raw materials to perform an amidation reaction and generate ammonium phthalamate; secondly adding sodium hydroxide solution to perform a displacement reaction and generate sodium phthalamate, removing ammonia molecules in the reaction solution, then adding methanol solution and sodium hypochlorite solution in the reaction solution to react and obtain paste methyl anthranilate, heating the paste methyl anthranilate to dissolve in water; and finally distilling the mixed liquid of methyl anthranilate and water to obtain methyl anthranilate. The methyl anthranilate prepared by the method of the invention has high content which is up to 98.4%; the appearance is good, the light transmittance of the product is 58.6%; the yield is high, which is increased by 0.4%-0.5% compared with the original technology; and the technology is advanced, the secondary recovery of ammonia water and methanol can be performed, and three wastes are not discharged in the production process.