Adenoid basal carcinomas of the uterine cervix are uncommon neoplasms and generally run a favorable clinical course. Although it is well known that these tumors do not evoke the stromal reaction, we immunohistochemically examined a stromal reaction in a case of adenoid basal carcinoma. A 40-year-old woman was found to have a cervical polyp during a medical checkup and underwent polypectomy. Histological examination revealed the finding of adenoid basal carcinoma. Immunohistochemically, a smaller number of CD34-positive and CD31-negative stromal cells, namely fibroblasts, in the stroma of tumor center than in normal cervical stroma were observed. On the other hand, alpha-smooth muscle actin-positive and h-caldesmon-negative stromal cells, namely myofibroblasts, were completely absent in the stroma of tumor center. Finally, our preliminary report suggests that the decrease of CD34-positive fibroblasts in adenoid basal carcinoma may show an early stromal reaction to tumor invasion. Gynecologists and pathologists should bear in mind that adenoid basal carcinoma may arise in a cervical polyp.