Abstract: Objective: To study the effect of different kinds of wear particles of prostheses on growth characteristics of cells at bone implant interface.Methods: Ti-6Al-4V, CoCr alloy and UHMWPE particles suspension at a concentration of 0.5 and 1.5 mg/ml（W/V） was separately added into synoviocyte system of normal human hip joint in vitro. The growth curves and doubling time of synoviocytes were compared and toxicity reaction of cells to particles was observed. Results: UHMWPE particles could accelerate the growth of synoviocytes. The doubling time was 24.9 hours versus 25.3 hours of control. Ti-6Al-4V particles inhibited cell growth at the early stage, but the amount of cells began to increase continuously since the fourth day with a doubling time of 32.7 hours. CoCr particles showed a toxicity effect on cells with relation to particle concentration. The cells died out at the eighth day in the group of 1 5mg/ml. Conclusion: Particles of different material have different effects on synoviocytes. This appearance has some similarity with the reaction in the interface membrane around aseptically loosened prostheses.