Background: Wound healing is a complex process necessary to repairing damaged tissues and preventing infection. Selenium nanoparticles were known by their antioxidant and antimicrobial effect that is important in wound healing. Aim: the aim of this study was to investigate the effect of selenium nanoparticles in reducing and accelerating the wound healing time in mice. Methods: Se NPs were synthesized by a simple wet chemical method. Then the experimental animals were divided into the following groups: Negative control group, Positive control group, selenium nanoparticles control group, wounded mice treated with selenium nanoparticles group. At the end of experiment, mice were scarified&  skin tissue samples were collected for biological analysis [Vascular Endothelial cell Growth Factor, Collagenase I and Nitric oxide] and histopathological study. Results: The results showed that the percentage of wound area has been significantly reduced in Se NPs treated group compared to the positive control. The level of Vascular Endothelial Growth Factor and Collagenase I in Se NPs groups were significantly increased compared to positive control while nitric oxide was significantly decreased in Se NPs treated group. Skin tissue showed effect of selenium nanoparticles by regenerating and recavering skin layer. Conclusion: Selenium nanoparticles have an important role in accelerating and reducing wound healing time.