Purpose:To seek confirmation of the hypnosis influence on the stability of humans respiration motion.Methods:Six volunteers are taken in an experiment under three kinds of surrounding scene(Normal,Music-Background and Self-Hypnosis)respectively on this study.The state-of-the-art technology,Magnetic Resource Imaging(MRI),is applied to getting the respiration data of the lungs coronal plane of all volunteers under different surrounding scene.The distance from the apex of lung to diaphragm is generally regarded as the characteristic length in craniocaudal direction.Results:By analyzing the amplitudes of respiration motion wave data,it is found that the amplitudes of volunteers under Self-Hypnosis scene is lower than those in Normal scene and Music-Background scene.Compared with the Normal scene,the volunteers amplitudes is 6.7mm lower averagely and has an average of 21.8%deduction in Self-Hypnosis scene.Meanwhile,the amplitudes is 3.4mm lower averagely in Self-Hypnosis scene than in Music-Background scene,with an average deduction of 4.2%.In addition,the fluctuation of the amplitudes wave is more stable.The standard deviation(Std)of amplitudes in Self-Hypnosis scene significantly reduce 24.7%and 28.1%averagely in comparison with those in Normal scene and Music-Background scene.Conclusion:The above observations show that volunteers in hypnosis state have smaller respiratory motion amplitudes and Std,which provides more objective evidence for the statement that hypnosis helps to shrink the operational range and improve the accuracy of target range when doctor performs surgery or therapy for cancer illnesses,thus providing valuable references in radiotherapy for lung cancer.