Background: the aim of this study is to assess the bonding efficiency of resin composite using self etch adhesive to dental tissues after remineralization with Nano bioactive glass. Materials and methods: A total number of 25 extracted caries-free human permanent molars used. 5 specimens as a positive control (sound dentin), the remaining 20 specimens demineralized. The demineralized dentin divided into: 5 specimens' negative control (demineralized dentin) and the remaining 15 specimens divided into 3 groups (5 each) according to the period of application of Nano bioactive glass particles either one day, one week and one month. Resin composite was bonded to the tooth surface wether enamel or dentin using universal self-etch adhesive and the teeth were tested for microshear bond strength using a universal testing machine. Results: Nano bioactive glass showed statistically significant lower results than sound dentin and higher results than demineralized dentin. Different times of application showed more remineralization effect with the highest effect for the one-month application. Conclusion: Nano bioactive glass as remineralizing agent improved the bond strength after remineralization and the effect is greater with time.