Abstract: The cyclic strain and stress of 304L stainless steel welded specimens were investigated on material testing system.To simulate the vibratory stress relief(VSR) processing,the tensile-compress cyclic loading was applied.The experimental results showed that the dynamic strain has feature of cyclic creep.Cyclic loading affected the creep and creep speed.The bigger the loading,the bigger the creep and the creep speed,and the longer time that the strain became stable.The residual stresses at weld toe were measured using X-ray diffraction method after different cyclic stress amplitude.According to the experimental results,the cyclic creep mechanism during VSR processing was presented.