As dental implant technology becomes increasingly widespread, peri-implantitis induced bone resorption and implant loss have garnered significant academic attention. Current clinical treatments for peri-implantitis primarily focus on plaque control, but the limitations of traditional therapies often hinder effective outcomes. Treatment strategies targeting immune responses that can eliminate inflammation, control osteolytic environments, and restore physiological bone formation are promising approaches. This article comprehensively reviews the role of the immune system in the pathogenesis and progression of peri-implantitis through a synthesis of multiple literature sources. It introduces current immunomodulatory strategies in the treatment of peri-implantitis and discusses the potential applications and challenges of novel immunotherapies, including gene therapy, cell engineering, and nanotechnology, in the management of peri-implantitis. The aim is to provide guidance for translating immunotherapies from the laboratory to clinical practice.