To evaluate the degree of microleakage in restorative materials, namely Glass Ionomer Cement (GIC), Resin-Modified Glass Ionomer Cement (RMGIC), and Ormocer, using an in-vitro approach. Materials and Methods: Standardized Class I cavities were prepared on extracted human molars and divided into three groups (n=10) based on the restorative material used: GIC (Group 1), RMGIC (Group 2), and Ormocer (Group 3). The cavities were filled with respective materials following manufacturers' instructions. All specimens underwent thermocycling to simulate oral conditions. Subsequently, teeth were immersed in a dye solution for 24 hours, sectioned buccolingually, and examined under a stereomicroscope to evaluate dye penetration, indicating microleakage. The extent of microleakage was scored and statistically analyzed using appropriate tests. Results: Analysis revealed varying degrees of microleakage among the different materials. GIC exhibited the highest microleakage, followed by RMGIC, with Ormocer showing the least. Statistical significance was found between the groups (p<0.05). Conclusion: Within the limitations of the study, Ormocer demonstrated superior resistance to microleakage compared to GIC and RMGIC. These findings suggest that Ormocer may provide a better seal and durability, potentially leading to improved clinical outcomes. However, clinical trials are necessary to confirm these results under in-vivo conditions.