Background: Deproteinizing enamel with sodium hypochlorite proved its positive effect when applied before one of the recent remineralizing agents (self-assembling peptide) which is considered an ideal enamel biomimetic approach. Objectives: To investigate the effect of sodium hypochlorite on the remineralizing capacity of the self-assembling peptide when applied before versus after acid etching of enamel; and the ability of the self-assembling peptide to sustain the remineralizing effect. Materials and Methods: Artificial enamel lesions were created on the proximal surfaces of 64 sample. Specimens were randomly put into two groups (N=32) according to NaOCl sequence of application (before/after acid etching). Group S1 (NaOCl applied before acid etching as recommended by the manufacturer); Group S2 (NaOCl applied after acid etching). After that, enamel samples were subjected to a pH-cycling for 1 month, followed by 3 months. Surface microhardness (SMH) was assessed at baseline, after demineralization, after remineralization, after pH-cycling for 1 month, and 3 months. SMH values were analyzed using ANOVA, the percentage of change of SMH was calculated based on the baseline SMH; the lower the value of the percentage of change the better the remineralizing capacity. Results: Upon comparing the values of percentage of change of microhardness at different timings we found that the lowest statistically significant percentage of change belonged to group S2. Conclusion: The sequence of NaOCl application had a statistically significant effect when applied after acid etching on the remineralization capacity of self-assembling peptide during different times of measuring leading to better re-hardening action and sustainable remineralizing action.