MiR-7 has been recognized as an osteoarthritis (OA) promoting factor, but thespecific down-stream pathway of miR-7 still remains unknown. Further investigationof the molecular regulatory mechanism of miR-7 might help develop a novel therapeutic method for OA. In this study, we revealed that Semaphorin 6D(SEMA6D) was a direct target gene of miR-7, and presented a negative regulatory relationwithSEMA6D in vitro and in vivo. SEMA6D could improve OA in rat OAmodels, asindicated by H&E and Safranin O-Fast green staining, and also µCT analysis. Further evaluation of SEMA6D suggested that SEMA6D promotes the anabolismand reducesthe catabolism of C28/I2 chondrocytes via inhibiting the activation of the p38pathway. The present research illustrated that SEMA6D is a negatively regulatoryfactor of miR-7 and a pivotal mediator of catabolism and anabolismin C28/I2chondrocytes. SEMA6D exerts its function via inhibiting the activation of the p38pathway.