Preheating is crucial in welding high-strength steels as it reduces the risk of cold cracking, manages residual stresses, and improves the mechanical properties of welded joints. This study examines various preheating techniques and their effects on the temperature field, residual stress distribution, and deformation behavior in high-strength steel welding. The specific procedures for enhancing it are discussed in this paper, focusing mainly on preheating, controlled heat input during welding, and additionally heat treatment of the welded joint. Through experimental analysis, the optimal preheating temperatures and methods for different steel grades, including S960QL and S1100M, are determined. The results indicate that preheating significantly lowers residual stress, prevents brittle fractures, and enhances overall weld quality.