Abstract: In this paper, BTNM450-Re and BTNM450 test materials were selected to analyze the effects of rare earth element Ce on the weldability of wear-resistant steel from the microstructures, mechanical properties, welding continuous cooling transformation behavior and thermal simulation results of welding heat affected zone toughness. The results show that the martensite content of BTNM450-RE plate increases after the addition of rare earth element Ce. Under the same welding thermal cycle conditions, the martensitic structure in the superheated zone of BTNM450-Re steel lasts longer, the martensitic transition end temperature is higher than that of BTNM450 steel, and the hardness in the superheated zone is generally higher than that of BTNM450 steel. The hardenability of BTNM450-Re steel is better than that of BTNM450 steel, the microstructure of the welding heat affected zone is ideal, and the hardness and toughness are better than that of BTNM450 steel. The resistance of BTNM450-Re steel to hydrogen cooling crack is better than that of BTNM450 steel, and its hardening tendency is higher than that of BTNM450 steel.