The invention relates to a cutting device capable of improving parallelism of two ends of a core. The problems that when an existing core cutting device is used for cutting, parallelism of two ends of a core is hard to grasp, and machining quality is poor are mainly solved. The cutting device is characterized in that a water tank bottom plate (55) is fixed in a case (45), a grinding wheel body (57) is fixed to the upper portion of the water tank bottom plate (55) through a grinding wheel fixing plate (56), the two sides of the grinding wheel body (57) are connected with a cutting disc (53) and a cutting and grinding wheel (60) through a rotating shaft, and core feeding devices are fixed to the portions, on the two sides of the grinding wheel fixing plate (56), of the water tank bottom plate (55) respectively. When the cutting device is used for cutting the core, the two ends of the core can be cut without disassembling, parallelism is improved, the clamping frequency is reduced, and machining efficiency is improved.