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Aim: To determine the apoptotic effect of recombinant rat Fas Ligand on rat intervertebral disc cells pre-treated with IL-lbeta in vitro, and the expression of Fas in cultured rat intervertebral disc cells. Methods: Cells were isolated from the inner annulus fibrosus and transition zones of lumbar discs from Sprague-Dawley rats.The cells were grown in monolayer and divided in 5 treatment groups. IL- lbeta (10 ng/mL), FasL (5, 20 ng/mL) with/without IL-lbeta (10 ng/mL) pre-treatment was respectively added in Dulbecco’s modified Eagle’s medium and Ham’s F-12 medium with 1% fetal bovine serum. After 32 h, the cells were stained with annexin V-FITC and propidium iodide to evaluate apoptosis using flow cytometry and to analysis transcription of Fas using RT-PCR. Results: Compared with control group, FasL (20 ng/mL), IL- 1β (10 ng/mL)+FasL (5 ng/mL), and IL- 1β ( 10 ng/mL)+FasL (20 ng/mL) induced significant apoptosis of the disc cells (P<0.01).Apoptosis was also induced by FasL 5 ng/mL (P<0.05); whereas, apoptosis was not induced by IL- 1β ( 10 ng/mL) (P>0.05). IL- 1β (10 ng/mL) enhanced the apoptosis-inducing effects of FasL (5 ng/mL) and FasL (20 ng/mL) in disc cells. Fas gene transcription in all groups and Fas expression in the 5 treatment groups were approximately 1.2-2. 1-fold greater than control group (respectively, P<0.05).Additionally, Fas expression in FasL with IL- 1β pre-treatment groups were signifi-cantly up-regulated than in FasL groups (P<0.01). Conclusion: The results of this study showed disc cells pre-treated with IL-lbeta increased apoptotic rate in response to FasL in vitro and provided insights to understand Fas/FasL system-mediated apoptosis in disc cells which would be enhanced due to inflammation factor in degenerative disc.