Aim: To evaluate the efficacy of three commercially available fluoride varnishes on the artificially induced carious lesion of the permanent premolars teeth and their resistance to further demineralization. Material and Methods:Sixty extracted permanent premolars were divided mesiodistally into two halves (n=120). The samples were divided into two equal groups (n=60); GI and GII, each main group was divided randomly into three subgroups according to the type of fluoride varnish. Subgroup a (MI varnish), subgroup b (Enamel Pro varnish) and subgroup c (Clinpro White varnish). The samples of GII only were immersed in demineralizing solution for 96h to create artificial caries. Application of fluoride varnishes respectively to all samples of GI and GII. The samples were examined by using Stereomicroscope, SEM and Vickers' microhardness test. The samples of two groups were immersed again in demineralizing solution for 96h to evaluate the resistance to carious lesion. Examination tests were used again. Results:All remineralizingagents increased VMH values, Clinpro White varnish was better in GI than other types but in GII, Enamel Pro was better in VMH values and structurally. Conclusions: All of the three fluoride varnishes are capable to remineralize early carious lesions.