These findings showed that Radix Hedysari polybotrys flavonoids could inhibit the expression of matrix metalloproteinase 2 (MMP2) and tissue inhibitor of metalloproteinase-1 (TIMP-1), contributing to a balance between MMPs and TIMPs and suppressing the progression of pulmonary fibrosis. The gene discussed is TIMP1; the disease is pulmonary fibrosis.