Estrogen is a steroid hormone produced by the ovaries. Estrogen is a hormone that triggers collagensynthesis by fibroblast.Collagen has affects for thickness of dermis.Estrogen deficiency can lead disruptioncollagen synthesis, so has an impact on decline dermis thickness. Unilateral ovariectomy is the act ofremoval of one ovary in the female reproductive system and is a model for estrogen deficiency. Thecondition of estrogen deficiency can be overcome by giving phytoestrogens. Black soybean seed is one ofphytoestrogens source. The purpose of this study was to determine the effect of black soybean extract afterovariectomy on increasing on dermis thickness (Mus musculus L.). The dosage of black soybean ethanolextract used was 0.31 g / ml / day and 0.63 g / ml / day administered orally (gavage) for 20 days. The resultsshowed a dose of 0.31 g / ml / day may and 0.63 g / ml / day increase dermis thickness of mice.