Periodontal tissues, including the periodontium, cementum, and alveolar bone, are significantly lost in moderate to severe periodontitis. The WNT/β-catenin signaling pathway promotes the proliferation and differentiation of periodontal ligament cells, osteoblasts, and cementoblasts to maintain the periodontium and improve the formation and regeneration of the cementum and alveolar bone. This review summarizes the WNT/β-catenin signaling pathway and its effects on the formation and regeneration of periodontal tissues.