Objectives: This study was designed to evaluate and compare Fluoride versus Bioactive Glass effect on Enamel after Cold Light Activated Bleaching and Chemical Bleaching. Materials and Methods: Forty specimens obtained from ten sound bovine central incisors were numbered from 1 to 40 and subjected to EDAX &SEM analysis. Specimens were divided into two main groups, the first group was subjected to chemical bleaching using 35% hydrogen peroxide gel and the second group was subjected to cold light activated bleaching using 25% hydrogen peroxide gel. After bleaching, EDAX & SEM analysis for all specimens was done. Each main group was subdivided into two groups according to the remineralizing agent used. The first subgroup was treated by fluoride gel and the second was treated by bioactive glass gel for 3 minutes twice daily for 10 consecutive days. EDAX and SEM were done for all Specimens after remineralization. Results: Calcium and phosphorus levels were significantly decreased after bleaching with both chemical and cold light bleaching techniques. Ca &p levels were significantly increased after using fluoride or bioactive glass. Higher remineralization results were obtained with bioactive glass. Bleached enamel appeared porous with multiple surface irregularities which disappeared after using fluoride or bioactive glass. Conclusion: In-office bleaching has deleterious effect on enamel surface causing decrease of calcium and phosphorus which can be reversed by using remineralizing agents. Bioactive glass has superior effect than fluoride in restoring enamel minerals.