Background and objectives: Increasing prevalence of non-carious cervical lesions makes it imperative to overcome challenges in tooth preparation, isolation and restoration. Bio-active restorative materials are relatively new concepts in dentistry having the potential to prevent secondary caries, a major cause of failure of restorations. Composite resins have the disadvantage of polymerization shrinkage leading to marginal gap formation. This study evaluated the marginal microleakage properties of Activa bio-active composite resin using three different adhesives in non- carious cervical lesions. Materials and method: Forty extracted maxillary & mandibular premolars for the study were collected. The specimens were divided into groups (n= 10). Box type class V cavities, 2mm inciso-gingivally, 3mm mesio-distally & 2mm in depth was prepared on the buccal surfaces. Group 1: Activa bio-active resin +No bonding agent, Group 2: Activa bio-active resin +Tetric N-bond, Group 3: Activa bio-active resin +Single bond Universal, Group 4: Activa bio-active resin + G Premio bond. Restorations were done and samples subjected to thermocycling. They were immersed in Rhodamine B dye solution for 24 hours. The samples were longitudinally sectioned in a bucco-lingual direction with diamond discs, examined under a stereo-microscope with 30x magnification and depth of penetration analyzed. The statistical analysis for microleakage was performed using the Kruskal Wallis test followed by the Mann Whitney U-tests with the Wilcoxon correction for pair-wise comparisons at a significance level of p < 0.05. Results: Activa bio-active resin + G Premio bond showed lesser micro-leakage compared to other groups and the difference was statistically significant. Conclusion: Activa bioactive resin with G Premio bond, 8th generation bonding agent showed lesser micro-leakage when compared with 5th and 7th generation bonding agents.