3,4,5-trimethoxybenzoic acid is an important fine chemical product or drug intermediate, which is widely used in medicine, dye, food and fine chemical industry. 3,4,5-trimethoxybenzoic acid is the metabolite of trimebutine, which can be used as the impurity standard reference of trimebutine and used in the laboratory organic synthesis and chemical and pharmaceutical research and development process. It can also be used in the production of antibacterial synergist trimethoprim and anti anxiety drug trimethoxyline.