Abstract: The microalloying 414N (MA414N) welding wire via Ti/Nb/V and Ce was used to weld the hard-faced layer of continuous casting roller, and the oxidation and thermal shock resistance of the MA414N hard-faced layer were compared with 414N hard-faced layer without microalloying. Transmission electron microscope (TEM), scanning electron microscope (SEM)/energy disperse X-ray (EDX), and X-ray diffraction (XRD) techniques were used to investigate the effect of microalloying on oxidation and thermal shock resistance of the hard-faced layer and its mechanism. The results show that the oxidation and thermal shock resistance of MA414N is significantly improved, compared to that of 414N. After oxidation for 360 h at 650 °C, the oxidation weight gain and oxidation rate constant of MA414N are reduced by 16% and 31%, respectively, compared to 414N; the surface damage factor of MA414N after 300 thermal shock cycles is significantly reduced by 53% compared to 414N. The initiation and propagation of thermal shock-induced cracks are affected by thermal stress, microstructure stress, and oxidation. The significant improvement of thermal shock resistance of MA414N is mainly due to the strengthening of the second phase precipitation, less microstructure transformation between M and A, and a relatively stable oxide film structure.