Background: To investigate the effect of diode laser application and two commercial remineralizing agents on the remineralization and surface microhardness of white spot enamel lesions. Material and Methods: Sixty specimens were prepared then equally divided into six groups (n=10/group), according to the diode laser and the two commercial remineralizing agents applied to demineralized enamel surfaces (APF gel and sodium fluoride NaF mousse) with or without diode Laser application as follows; Group A; control, Group B; diode Laser application, Group C; APF gel application, Group D; NaF mousse application, Group E; APF gel application + diode Laser, Group F; NaF mousse application+ diode Laser. Then the teeth were investigated for their Ca, P & F ions content and surface microhardness. One-way ANOVA followed by Tukey's (HSD) post hoc test were used for statistical analysis. Results: Ca ion wt% showed no statistically significant difference between tested groups, with the highest mean value recorded with Group C. P ion wt%, showed a statistically significant difference between Groups A and C, and the highest mean value was recorded for Group A. The highest F ion wt% was recorded for Group C, while the lowest was recorded for both A and B groups. The highest significant microhardness mean values was recorded for Group E, while the lowest was recorded for Group A. Conclusions: diode Laser treatment of the demineralized enamel surface had a positive influence on the chemistry and surface microhardness and it may represent a promising adjunct for enamel surface remineralization.