The invention discloses an arm anti-shaking device applied to a Parkinson patient. The arm anti-shaking device comprises a wearing structure, an arm shaking sensing circuit board, a motor and a weighing block, wherein the wearing structure is worn on the arm; the arm shaking sensing circuit board, the motor and the weighing block are arranged inside the wearing structure; the arm shaking sensing circuit board comprises a PCB (printed circuit board) and a sensing circuit arranged on the PCB; the sensing circuit comprises a microprocessor, a motor driving module and a motion sensing module; the motor driving module is respectively connected with the microprocessor and the motor; the motion sensing module is connected with the microprocessor; the weighing block is fixed on an output rotating shaft of the motor. The arm shaking condition of a patient is sensed through the motion sensing module; after the processing by the microprocessor, the control motor drives the weighing block to do reverse motion, so that the goals of counteracting the arm shaking of the patient and stabilizing the arm balance of the patient can be achieved; the principle is simple; the realization is convenient; the arm anti-shaking device can be applied to patients of various people groups, is not influenced by the physical quality of the patient, and has the obvious effect.