Objective To study the effect of icariin on proliferation and phenotype of osteoblasts interfered with titanium particles. Methods Calvarial osteoblasts of newborn rats were cultured in vitro and cell identification was performed by alkaline phosphatase staining. Effect of titanium particles with different concentrations on osteoblasts proliferation was detected by CCK-8 method. Meanwhile , medium lethal concentration of titanium particles was screened out. Under this concentration , icariin with concentrations of 10-5, 10-6, 10-7, 10-8, 10-9 and 10-10 mol/L was added respectively for interference. The effect of icariin on proliferation of osteoblasts interfered with titanium particles was observed so as to obtain optimum drug concentration. Icariin with optimum concentraion was added into osteoblasts interfered with titanium particles. ALP activity of each group was detected by ELISA and calcified nodules were stained by alizarin S red to observe the effect of icariin on phenotype of osteoblasts. Results Titanium particles with different concentrations can inhibit proliferation of osteoblasts (P < 0.05), 0.5 mg/mL is its medium lethal concentration. Icariin can promote proliferation of osteoblasts interfered with particles (P < 0.05), the optimum drug concentration is 10-9 mol/L. With this concentration, icariin can significantly improve ALP activities of osteoblasts (P<0.05) and calcified nodules formation. Conclusion Icariin can promote proliferation and phenotypic expression of osteoblasts interfered with titanium particles. It may probably become an effective medicine for preventing aseptic joint prosthesis loosening.