The remanufacturing experiment of FV520B precipitation hardening stainless steel was carried out by using surfacing deposition technology. On this basis, the remanufacturing microstructure characteristics were analyzed and the effect of mechanical vibration on remanufacturing microstructure was studied. The results showed the following: Firstly, the remanufacturing microstructure of FV520B stainless steel by MAG surfacing deposition technology was comprised of martensite plus a carbide precipitation-hardening phase. It performed a characteristic periodical variation along the direction of forming height, which was described by certain self-similar fractal characteristics. The vibration would increase the probability of twin formation to some extent. There was also the broken effect on martensite lath that had to be taken into account. It should be noted that the width of the martensite lath decreased first and then increased with the continuous increase of the vibration rotation rate. Affected by the vibration, the lattice distortion and the preferred orientation of each crystal plane would both be changed. However, the change rule of different crystal planes was different. The Bragg diffraction peak positions of planes (110) and (211) shifted towards the direction of lower diffraction angle due to the addition of vibration. Furthermore, the offset increased first and then decreased with the continuous increase of the vibration speed. Meanwhile, the FWHM of diffraction peak (110) decreased first and then increased and the preferred orientation of this crystal plane increased first and then decreased. Within the range between 0 and the resonance speed, the FWHM of diffraction peak (211) decreased first and then increased with the continuous increase of the vibration speed and decreased again when the vibration speed was higher than the resonance speed. However, its preferred orientation continued to increase with the increase of the vibration rotation rate. In general, the sub-resonance frequency (The vibration rotational speed f=3000 r/min) had the most significant effect on the remanufacturing microstructure of FV520Bstainless steel by MAG surfacing deposition technology.