Objective：To use an in vivo titanium particles induced mouse calvarial osteolysis model to investigate the inhibitory effect of erythromycin and alendronate on the osteolysis． Methods：Forty female eight-week-old BALB/C mice were randomly divided into 5 groups 8 in each group. Control group （A） received sham operation；titanium particle group （B） received 30 mg titanium particle im－plantation onto the calvariae；alendronate group （C） received 30 mg titanium particle implantation and alendronate 0.3 mg/（kg·week－ly） by ip injection；one unit of erythromycin group （D） received 30 mg titanium particle implantation and ip injection of EM 2 mg/（kg·d） in the next week；two units of erythromycin group （E） received ip injection of EM 2 mg/（kg·d） on the next day of 30 mg ti－tanium particles implantation；two weeks later mouse clvariae were harvested. The EM and ALN efficacy was evaluated by Micro-CT and histology. Results：Micro-CT analysis showed that bone mineral density （BMD） and bone volume percentage （BVF） were sig－nificantly higher in the EM，ALN treated group（CDE） compared to the Ti group（B）（P<0.05）；BMD and BVF were significantly high－er in the Control group （A） compared to the Ti group（B）（P<0.05）. Histology analysis had a similar result with BMD. Conclusion：Erythromycin and alendronate can effectively inhibite titanium particles induced calvarial osteolysis in vivo.