Forty nine consecutive mastectomy patients were randomized to one of two groups. Twenty four patients had skin flaps created with the cold scalpel and twenty five with the electrocautery. The two groups were similar with respect to age, stage of disease, size of tumor, and weight. Cautery patients had significantly less operative blood loss when compared with scalpel patients, 352 versus 507 milliliters, respectively, P less than 0.05. No cautery patient required transfusion compared with three transfused scalpel patients, P less than .005. Total postoperative hemovac drainage and hospital stay were not significantly different between the two groups. Although the number of fever days and wound complications were slightly higher in the cautery group, the difference was not statistically significant. The electrocautery may be superior to the scalpel for mastectomy.