This study was conducted to evaluate the effect of using two different remeniralizing agents prior to the use of adhesive system on shear bond strength of the nano-hybrid composite resin. A total of 84 extracted molar teeth used maximally two months after extraction. The exclusion criteria for selection of the samples were the teeth with caries, cracks, erosion, fluorosis or hypo-calcification, and restorations.A flat dentin surface was prepared perpendicular to the longitudinal axis of each tooth using a low-speed Isomet diamond saw under water-cooling. Teeth were randomly divided into three main groups; each group had 28 tooth randomly selected. First group (A1) (control group) had no re-mineralizing agent. Second group demonstrated fluoride varnish (A2 group). The third group demonstrated tri-calcium phosphate varnish (A3 group). Acid etching applied to all groups, also self-etch adhesive system. A metal mold was used to build up composite resin buttons of 2mm thickness and 2mm in diameter, light cured for 40 sec to all groups according to the manufacturer instructions. Each group subdivided into two other groups according to the time of testing; (T1, T2 groups) after one week and three months respectively. All samples were tested by universal testing machine.Shear test was done by compressive mode of load applied at tooth-resin interface via mono-beveled chisel attached to the upper movable compartment of testing machine. The cross-head speed of the machine was set at 0.5 mm/min. The load required to debonding was recorded in MPa by the aid of computer software.The raw result data has excluded extreme values to keep the standard deviation as normal value. These extreme values were very high for the TCP groups and were very low for the other groups.The result showed that the third intervention group (A3) was the highest shear bond strength value irrespective to testing time followed by the second intervention group at one week (A2T1). In the second hand the control group showed the least shear bond strength value while no remeniralizing agent was used.Conclusion: Fluoride varnish and TCP has no difference in dentin re-mineralization. Using remeniralizing agent before application of bonding system tends to increase shear bond strength. TCP has attendance as a remeniralizing agent prior to adhesion to demineralized dentin that can protect shear bond strength’s value from dropping after three months storage in aqueous media.