The invention provides a device for simulating borne force of a machine tool cutter. The device for simulating the borne force of the machine tool cutter comprises a clamping mechanism, radial feeding mechanisms and a simulating cutter. The simulating cutter comprises a simulating cutter connecting end and a simulating cutter force bearing end. The simulating cutter connecting end is connected with a rotating cutter seat of a tested machine tool. The clamping mechanism is used for clamping the simulating cutter force bearing end and does not limit circumferential rotation. The radial feeding mechanisms each comprise a radial feeding fixed end and a radial feeding moving end. The radial feeding fixed ends are arranged on a worktable of the tested machine tool. The radial feeding moving ends are connected with the clamping mechanism. The radial feeding moving ends can move relative to the radial feeding fixed ends in the radial direction of the simulating cutter. According to the device for simulating the borne force of the machine tool cutter, the borne force in the process of machine tool machining can be simulated realistically without the need of consuming raw materials and the cutter in the performance testing process of the machine tool, the tested result is reliable, and the test cost is low.