A case of angiomyofibroblastoma of the vulva in a 53-year-old woman was examined by means of immunohistochemistry. Histological examination of the tumor revealed typical characteristics of vulval angiomyofibroblastoma. Immunohistochemistry of the tumor cells revealed diffuse immunoreactivity for estrogen receptors, progesterone receptors, vimentin, and CD34. The stains for cytokeratin, epithelial membrane antigen, desmin, smooth muscle alpha-actin, muscle-specific actin, and S-100 were negative. These results were mostly consistent with those of previous reports and suggest that the tumors cells were derived from primitive mesenchymal cells which occur normally in this lesion and which show the potential for diverse lines of myoid differentiation.