Purpose This paper aims to investigate the effect of simulated body fluid (SBF) on biodegradation and tribological properties of ultrahigh molecular weight polyethylene (UHMWPE) and UHMWPE stabilized with alpha-tocopherol. Design/methodology/approach The samples of UHMWPE and UHMWPE stabilized with alpha-tocopherol were prepared by a hot-pressing method, and then immersed in SBF for one year. Tribological test was performed on a UMT-2 tribometer. Findings The crystallinity and tribological properties increased slightly after UHMWPE stabilized with alpha-tocopherol, whereas the O/C ration decreased slightly. The crystallinity and O/C ratio increased after all samples immersed in SBF for one year. This resulted in the deterioration of tribological properties and the wear mechanism change. The tribological properties change was smaller in UHMWPE stabilized with alpha-tocopherol than that in UHMWPE, because the oxidation resistance of UHMWPE was increased by alpha-tocopherol. Originality/value The results of the experimental studies demonstrated and compared the biodegradation behavior and tribological properties of UHMWPE, UHMWPE stabilized with alpha-tocopherol, and after they immersed in SBF for one year.