Abstract: Objective To meet the urgent demands for lightweight and precision shipbuilding, this study conducted an exploration of the application of low-power laser welding technology in ship construction. Methods Laser welding tests were conducted on typical ship materials, including EH36 carbon steel and L907A steel. The influence of key welding parameters on weld formation was analyzed. On this basis, taking typical thin-walled structures such as light bulkhead and wall-attached air duct in ships as application scenarios, simulator welding tests were carried out to quantitatively evaluate post-weld deformation behavior. Results The research results indicate that reasonable matching of welding parameters can significantly improve weld formation quality, resulting in an aesthetically pleasing weld surface and reliable internal quality, among which laser power has a particularly significant effect on penetration depth. The experiments found that adopting a symmetric welding sequence can effectively regulate heat distribution, significantly inhibit welding deformation of large-scale components, and maximize the maintenance of structural dimensional stability. Conclusion Low-power laser welding technology exhibits excellent deformation control capability and process stability in the welding of thin-walled ship structures. This study provides important process data and practical foundation for the standardization and engineering application of this technology in the shipbuilding industry.