Objective To investigate the control effect of micro-arc carburization on the surface recrystallization (RX) of a directionally solidified superalloy DZ125L. Methods After being deformed by shot-peening, the DZ125L samples were carburized by micro-arc carburization with graphite bars. And then they were heat treated with those samples that were shot-peened directly. Microstructure was characterized by optical microscopy (OM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Results Compared with surface recrystallization produced by direct shot-peening, the depth of surface recrystallization after microarc carburization combined with shot-peening accounted for only about 60% of samples without micro-arc carburization. The XRD analysis indicated that plenty of TiC and (Cr,Mo) 23 C6 were formed on the surface layer of alloy after micro-arc carburization treatment. Enrichment of Ti, Mo, W, Cr and C was found by energy dispersive spectroscopy ( EDS) analysis on the surface layer of carburization treated samples, which further indicated that plenty of carbides were formed. These carbides retarded the migration of RX grain boundary. Furthermore, micro-arc carburization strengthened the surface layer of alloy and the carbides covered the surface of the alloy, which made the deformed layer become smaller and suppressed the RX nucleation on the surface, and resulted in the smaller RX depth finally. Conclusion Therefore, RX can be suppressed effectively by micro-arc carburization treatment.