Background: There are a number of studies on transdermal drug delivery using microneedles. Microwound by using repeated microneedle stimulation might be involved in hair growth directly or indirectly through the wound healing process. Objectives: The purpose of this study was to determine the proper needle length and rolling cycles for hair growth and examine expression of hair growth related molecules. Methods: We designed experiment to know what will happen after repeated small injury using C57BL/6 mice. Disk type microneedle roller was used to evaluate the differences of hair growing effects according to microneedle length and rolling cycles. In addition, the change of hair growth related factors (Wnt3a, Wnt10b, β-catenin, VEGF) was checked. Determining the selected lengths and cycles in first experiment, we applied to each mice group during 4weeks and evaluated expression of hair growth related factors. Results: As a result, size of 0.5mm roller was the most effective in hair growth. Microneedle was affecting regulation of VEGF, Wnt3a, Wnt10b, β-catenin, markedly increased the expression of VEGF. Conclusion: Microwound by microneedle may be affect to hair growth and surrounding tissue angiogenesis.