Abstract: The Metal Magnetic Memory testing can be used to estimate stress of ferromagnetic materials and achieve early diagnosis. However, because of the lack of a unified theory on it and of the quantitative methods, this technology has not been recognized. In order to further understand the generation and accumulation mechanism, the ferromagnetic specimen(Q235) under cyclic loading was under study, and the technology of metal magnetic memory combined with the Magnetic Barkhausen noise was discussed. The results showed that the side of metal magnetic memory signal waveform was asymmetry and the side of the lager peak had an uneven distribution of the organizational structure, the peak would be changed obviously after cyclic loading. According to the change of distribution under cyclic loading, it offers a foundation for studying the relation between the signal of metal magnetic memory and stress concentration.