To evaluate the effect of proanthocyanidin in grape seed extract on the microtensile bond strength between a self-etch adhesive and NaOCl treated pulp chamber dentin. Twenty extracted human molar teeth, were opened access, irrigated with 17%EDTA, 5.25% NaOCl and distilled water. Specimens were divided into four groups, Group 1 no treatment; Groups 2-4 , treated followed by 30% proanthocyanidin, 10% sodium ascorbate or 2% chlorhexidine respectively. All specimens were filled the access with resin composite using self-etched adhesive. Specimens were sectioned and trimmed prepared for microtensile bond strength test. Twenty specimens in each group were subjected to a microtensile bond strength test. There was no significant difference in microtensile bond strength between group 2-4 and microtensile bond strengths in group 2-4 were significantly higher than the group 1 (p<0.05). The 30% proanthocyanidin from grape seed extract, 10% sodium ascorbate and 2% chlorhexidine improved microtensile bond strengths between a self-etch adhesive and dentin after NaOCl irrigation.