Objective:To evaluate the biocompatibility Abstract of a liquid of propolis. Methods:According to the relative Chinese national standards,the cytotoxicity of the propolis abstract was investigated by in vitro cell culture,agar diffusion test and the oral mucous membrane irritation response test in rabbits. Results:In the in vitro tests the propolis abstract showed grade 0 cytotoxicity. In the in vivo test the abstract did not result in any pathological change in oral mucous membrane.Conclusion:The propolis abstract is biocompatible.