As a crucial branch of additive manufacturing technology, laser additive manufacturing (LAM) has attracted significant attention in near-net-shape forming of metallic components due to its inherent advantages of high precision and elevated material utilization efficiency, finding extensive applications in advanced equipment manufacturing sectors including aerospace and biomedical industries. However, the inherent characteristics of LAM involving rapid cooling rates and non-equilibrium solidification tend to induce high-magnitude residual tensile stresses, which frequently lead to defect formation such as porosity and cracking, consequently constraining the mechanical performance and practical engineering applications of fabricated components. Laser shock peening (LSP) emerges as an effective surface enhancement technique that utilizes high-energy laser-induced shock waves to generate gradient residual compressive stress fields within material surface layers, thereby improving both microstructural characteristics and mechanical properties. This paper systematically reviews the fundamental principles of LSP technology, with particular focus on its tripartite applications in LAM-processed metallic materials: as post-processing treatment, off-situ processing, and in-situ processing strategy. Recent research advancements are critically analyzed from these three implementation perspectives, followed by prospective discussions on future development directions for LSP applications in laser additive manufacturing systems.