Given the pathological characteristics of chondrocytes in osteoarthritis, we focused on the effects of Mg2+ concentration on IL-1β, MMP13, a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5), metalloproteinase inhibitor 3 (TIMP3), and hypoxia-inducible factor 1-alpha (HIF-1α) in inflammatory chondrocytes. The gene discussed is MMP13; the disease is osteoarthritis.