Abstract: Objective To explore expressions of matrix metalloproteinase-1 (MMP-1), tissue inhibitor of metalloproteinases-1 (TIMP-1) and transforming growth factor-β1 (TGF-β1) in valve tissue of rheumatic heart disease (RHD), and to analyzed their roles in RHD. Methods The expressions of MMP-1, TIMP-1 and TGF-β1 proteins and mRNAs were tested by Western blot and RT-PCR methods in valve tissues in participants with (experimental group, n=30) and without RHD (control group, n=15). Collagen fibers were detected by Masson staining, and collagen volume fraction (CVF) was caculated. The correlations of CVF and the expressions of MMP-1, TIMP-1 and TGF-β1 were analyzed. Results The collagen fibers, CVF, and the protein and mRNA expressions of MMP-1 and TGF-β1 in experimental group were higher than those in control group, while the protein and mRNA expressions of TIMP-1 in experimental group were lower than those in control group. The expression of TIMP-1 was negatively correlated with TGF-β1 and CVF in valve tissues, while MMP-1 was positively correlated with them. The expression of TGF-β1 was positively correlated with CVF in valve tissues. Conclusion MMP-1, TIMP-1 and TGF-β1 contribute to the progression of fibrosis in RHD.