Summary Osthole has potential therapeutic applications due to its antiosteoporotic. Our study suggested that osthole attenuates osteoclast formation by stimulating the activation of β-catenin-OPG signaling and could be a potential agent to inhibit bone resorption. Introduction Osthole has potential therapeutic applications due to its antiosteoporotic. we performed study to test if OPG is the target gene of osthole-attenuated osteoclastogenesis. Methods In vivo, using 12-month-old male mice to evaluate the effect of osthole on bone mass. In vitro, Bone marrow stem cells (BMSCs) were isolated, extracted from 3-month-old C57BL/6J mice, 3-month-old β-cateninfx/fx mice, or 3-month-old OPG−/− mice and its littermates of OPG+/+ mice. Results we found that osthole significantly increased the gene and protein levels of OPG expression in primary BMSCs dose-dependently. The deletion of the OPG gene did not affect β-catenin expression and the deletion of the β-catenin gene inhibited OPG expression in BMSCs, which indicated that osthole stimulated the expression of OPG through activation of β-catenin signaling. Conclusion Osthole attenuates osteoclast formation by stimulating the activation of β-catenin-OPG signaling and could be a potential agent to inhibit bone resorption.