Purpose: To evaluate the antibacterial effect of Bioactive composite versus Glass ionomer using different storage media. Materials and Methods: Three restorative materials were used in this study (Reliafil Lc, Amalgomer and Conventional Glass Ionomer). 90 Disk- shaped specimens (2.5 mm height and 8 mm diameter) were prepared from each material. Groups were divided into three subgroups according to storage media (Acids, artificial saliva and de-ionized water). Bacterial strains were polished at 370c for 24h in Brain Heart Infusion broth which attained from stock cultures. Disk diffusion agar method was used for antimicrobial liability. The inhibition zone diameter around the specimen were measured at three times by the same operator after 48hs using electronic digital caliper. Results: This study found that Amalgomer has the highest antibacterial effect in lactic acid. Whereas, Conventional GIC has the highest antibacterial effect in artificial saliva and Bioactive composite in deionized water. Conclusion: This study was concluded that all the restorative material tested had an antibacterial effect in all storage media though Amalgomer seemed to be more prominent in lactic acid.