TNF-alpha has long been implicated in the progression of rheumatoid arthritis (RA). However, how the receptors of TNF-alpha, namely TNFR1 and TNFR2, mediate TNF-alpha-induced inflammatory responses in fibroblast-like synoviocytes (FLS) in RA has not been elucidated. In the present study, primary FLS cells were isolated from RA patients and treated with TNF-alpha in vitro. The exogenous TNF-alpha induced the expression and release of endogenous TNF-alpha in FLS. In addition, TNF-alpha led to gradual downregulation of TNFR1 following 1 h treatment. By contrast, the expression of TNFR2 was markedly upregulated after 12 h treatment with TNF-alpha. Moreover, following TNF-alpha treatment, the expression of interleukin (IL)-2, IL-6, and IL-8 was gradually increased with time, but their mRNA levels dropped significantly at 48 h. We further investigated the differential functions of TNFR1 and TNFR2 in FLS by conducting siRNA-mediated knockdown. The TNF-alpha autocrine was inhibited to a greater extent in TNFR1-silenced FLS compared with TNFR2-silenced FLS. Silencing of TNFR1, not TNFR2, activated intrinsic apoptosis and inhibited TNF-alpha-induced cytokine production in FLS. These results suggest that TNFR1 is the major pro-inflammatory mediator of TNF-alpha in FLS, whereas TNFR2, which is upregulated in response to prolonged TNF-alpha stimulation, may act as an immunosuppressor in FLS for the prevention of overwhelming inflammatory reactions.