Objective: The aim of this study was to evaluate and compare the marginal adap‌tation of class V cavities restored with Alkasite, Bulk-fil Resin Composite (BFRC), resin-modified glass ionomer (RMGI), and conventional high viscosity glass ionomer (HVGI) restorative materials. Materials and Methods: Fifty Class V cavities (2 mm deep, 3 mm in width, and 3 mm in height) were prepared in sound extracted human molar teeth, where the coronal margins were in enamel while the cervical margins were at CEJ. Four different restorative materials were tested (n = 10): Alkasite (Cention), BFRC (Tetric N ceram Bulkfil), RMGI (Fuji II LC), and HVGI (Equia Forte). The teeth were evaluated for their marginal adaptation with SEM after thermocycling. Results: One Way ANOVA test was used to compare among all the restorative materials and showed significant differences. Student t test was used to compare between enamel and dentin margins showing significant differences for all groups. Conclusion: Alkasite-based restorative material had the ability to ensure tooth/restoration seal and preserve margin integrity.