The invention relates to a benzbromarone crystal form A applicable to the field of chemical pharmacy and a preparation method thereof. In an X-ray powder diffraction pattern represented by a 2theta angle, the error range of the 2theta angle is +/- 0.2. The benzbromarone crystal form A has the basic X-ray powder diffraction pattern. In the differential scanning calorimetry pattern, when the heating speed is 10 DEG C per minute, the benzbromarone crystal form A has a maximal endothermic peak, and the melting point value of the benzbromarone crystal form A is 152.23 DEG C. The method comprises the following steps: under the condition of 25 DEG C, taking 1.0g of benzbromarone crystal form A, and adding 10ml of trichloromethane, wherein the solid is completely dissolved, and the solution is clear; taking 1.25g of benzbromarone crystal form A, and adding 25ml of N,N-dimethylformamide, wherein the solid is slightly insoluble, and the solution is not clear; and crystallizing from a single solvent acetone to obtain the benzbromarone crystal form A. The crystal form has the advantages of high stability, simple preparation method, low cost, simple after-treatment, high product purity and fewer related substances.