Abstract: Objective This study aims to solve the problems such as nitrogen pores that tend to occur in the welded joints of a new type of ocean engineering stainless steel (OESS) fabricated by conventional fusion welding. In this paper, laser welding is used to study the effect of welding speeds on the microstructure and properties of welded joints, so as to reduce nitrogen loss and improve joint reliability. Methods The microstructure and properties evolution of welded joints at different welding speeds are characterized by macroscopic morphology observation, microstructure analysis, mechanical property testing and corrosion resistance testing, which provides experimental basis for optimizing OESS welding process parameters. Results The results show that the microstructure of welded joints at different welding speeds is austenite and a small amount of ferrite, and the micromorphology is mainly columnar grains. When the welding speed is 9 mm/s, the weld has the highest hardness of 305 HV, the tensile strength of weld is the maximum at 892.3 MPa, and the tensile fracture shows obvious characteristics of deep dimple fracture, the weld also has the best corrosion resistance, with a corrosion potential of −0.170 V and a corrosion current density of 1.30×10⁻⁵ A/cm². Conclusion This study confirms that laser welding technology can effectively control the nitrogen loss during OESS welding, significantly improve the welded joint performance, and is expected to promote the application of the OESS in field of marine engineering.