The invention discloses a cylindrical cam excitation driven bending-torsional coupling resonance type residual stress relieving device, and relates to a cylindrical cam transmission type alternated force moment bending-torsional coupling resonance type vibratory stress relief method. Torsional vibration output by a cylindrical cam transmission type alternated force moment torsional vibration exciter is applied to a high-rigidity rotary shaft, when the rotating frequency of the rotary shaft is equal to the difference of the natural bending frequency and the natural torsion frequency, based on the bending-torsional coupling resonance theory, namely, torsional vibration excitation with the frequency equal to the natural torsion frequency can excite bending resonance, meanwhile, the bending resonance and the torsional resonance are mutually strengthened, and enough dynamic stress is generated to eliminate the residual stress of the high-rigidity rotary shaft. According to the residual stress relieving device, the problem that bending-torsional coupling resonance vibratory stress relief is limited by a torsional vibration excitation source is solved, the residual stress of the high-rigidity rotary shaft is eliminated through cylindrical cam transmission type alternated force moment bending-torsional coupling resonance, the efficiency is improve, and the safety and reliability of production are improved.