ABSTRACT Introduction: Caries detecting dyes are solutions employed to differentiate the infected portion of carious dentin from the remineralizable affected dentin. However, it is important that these agents should not interfere with the adhesion of permanent restorative materials. Aim: The purpose of this study was to evaluate the effect of caries detecting solution on microleakage of composite resin restoration bonded with two adhesive systems. Materials and Methods: Class V cavity of standardised dimension was prepared on forty intact extracted molars. Out of this, 10 teeth each were randomly selected for the four study groups. Group 1: composite restoration after etch and rinse technique without any prior exposure to caries disclosing solution; Group 2: placement of the restoration as mentioned in group 1 after exposing the cavity with caries detecting solution; Group 3: cervical restoration with composite after the use of self-etch adhesive system, with no exposure to caries detecting dye; Group 4: Similar to group 3 except that caries disclosing agent was applied onto the class V cavity before the placement of the composite restoration. The amount of dye penetrated was evaluated using fluorescent microscope. The microleakage scores were recorded and data obtained were subjected to statistical analysis using the chi-square test. Results: No significant difference was detected between the groups (p>0.05). However, Group 3 (self-etch without dye) showed the least percentage of microleakage with none of the restorations showing grade 3 leakage score. Conclusion: All study groups showed microleakage, but there was no statistically significant difference between the leakage scores. However, the highest leakage was seen in the total etch group where caries detecting dye was used.