The invention discloses a turning force measuring device and a turning force measurement method and belongs to the field of machining and detection. The turning force measuring device comprises a force measurement sensor, a charge amplifier and a data acquisition unit, wherein the force measurement sensor is mounted inside a mounting groove of a cutter bar; the output end of the force measurement sensor is connected with the input end of the charge amplifier; the output end of the charge amplifier is connected with the input end of the data acquisition unit; when the turning force measuring device is used for measuring a turning force, one mounting groove is formed in the cutter bar and the force measurement sensor is mounted inside the mounting groove of the cutter bar. In the turning force measuring device disclosed by the invention, the force measurement sensor is relatively small in size, so the turning force measuring device is not restricted with a machine tool structure, a clamp, the space and the like, and is good in universality. By adopting the turning force measuring device disclosed by the invention, an expensive force measuring instrument is not needed, so the cost is lowered; meanwhile, when the device is used for measuring the turning force, a cutter can be normally clamped without extending a relatively long distance, so the rigidity of a cutter system during a cutting process is guaranteed.