Objective  To investigate the correlation between the expression of hypoxia-inducible factor-1α (HIF-1α) and the expression of matrix metalloproteinases (MMPs) in synovial tissues of patients with rheumatoid arthritis (RA). Methods  The  expressions of HIF-1α and MMPs in synovial tissues of patients with RA and osteoarthritis (OA) were detected by real-time PCR and the correlation analysis was conducted. Results  The mRNA expressions of HIF-1α, MMP-1, MMP-3, MMP-9, and MMP-13 in synovial tissues of patients with RA were significantly higher than those of patients with OA. Highly expressed HIF-1α in synovial tissues of patients with RA significantly and positively correlated with MMP-9. Conclusion  Highly expressed HIF-1α in synovial tissues of patients with RA may involve in the regulation of the expression of MMP-9 and the process of pathological change of RA.