The vascular supply of the skin of the hypothenar region was investigated using 12 cadavers and 24 hands. The ramifications of the proper palmar digital artery of the little finger were also investigated by angiogram in 20 hands. It was found that it is possible to raise the hypothenar skin as an island flap, using the reverse vascular pedicle of the proper palmar digital artery of the little finger. We applied this island flap in three cases. With the result of these anatomical and radiological studies, the details of three cases are described.