A new drug cocrystal CBZ-MTG was synthesed by using carbamazepine (CBZ) as a active pharmaceutical ingredient (API) and methyl gallate (MTG) as a cocrystal coformer (CCF) at room temperature. The crystal structure was investigated by X-ray single crystal diffraction, and the cocrystal was characterized by infrared spectroscopy, X-ray powder diffraction, thermogravimetric analysis and differential scanning calorimetry. In addition, the solubility was measured by HPLC and the stability was also tested. The cocrystal have been significantly improved in the aspect of solubility and bioavailability. The characterization of various structural properties provides the basic data and theoretical basis for its application in the field of drugs, and provides a new choice for carbamazepine-methyl gallate cocrystal as drug applications and in the preparation field.