Purpose: The purpose of the study was to assess the enamel remineralization potential of two bioactive glass- based toothpastes: Biomin® based toothpaste in comparison with Novamin® based toothpaste with sodium fluoride. Material and methods: Forty premolars were selected and divided equally into two groups named Novamin and Biomin groups after discarding their roots. First, the samples were soaked in a demineralizing solution for three days to get white spot lesion. Then, after rinsing them with deionized water, toothpastes were applied in the form of slurry twice daily, for two minutes each. The remineralization process lasted for two weeks. Environmental Scanning Electron Microscope (ESEM) was used to assess the remineralization degree. It was attached to Energy-dispersive X-ray spectroscopy (EDX) unit to measure the Ca, P weight percent and also the Ca: P for each sample. Three EDX readings were taken for each sample; baseline, after demineralization and after remineralization. Results: The results showed that both toothpastes have remineralization potential without statistically significant difference between them except in phosphate weight percent which was higher in the Biomin group. Conclusions: Within the limitations of the present study we concluded that the mineral content of the demineralized enamel significantly increase with using both Biomin and Novamin containing toothpastes twice daily for two weeks. Biomin may be more effective than Novamin in remineralization of demineralized enamel.