To describe the intramuscular neurovascular anatomy of the rectus femoris muscle and to evaluate whether the muscle can be split into two functional units, 40 rectus femoris muscle specimens were studied. Ten fresh human cadavers were injected with a mixture of lead oxide, gelatin, and water through the femoral arteries. The rectus femoris muscle with its neurovascular pedicles was dissected out and then radiographed. Computer wire was sutured to each nerve branch in the muscle, and the muscle was radiographed again. Radiographs with and without radiopaque wire were then analyzed. In 10 preserved cadavers, the rectus femoris muscle was dissected out. Note was made of the vessel and nerve to the muscle. All muscles were cut serially into 2-cm cross-sections, and the position and course of the intramuscular tendon were then grossly examined. Three different vascular patterns in 40 rectus femoris muscles were found, based on the number of vascular pedicles and their relative dominance within the muscle. The rectus femoris muscle received either a single vascular pedicle (12.5 percent), a dominant vascular pedicle and one or two minor pedicles (80 percent), or two dominant vascular pedicles (7.5 percent). The rectus femoris was innervated by a large nerve branch from the posterior division of the femoral nerve, and the branch generally divided into two sub-branches before it reached the muscle. Both branches were respectively accompanied by arterial branches to form neurovascular hila. Furthermore, this present study has provided a detailed description of the intramuscular neurovascular territories. Also, the pattern of neurovascular supply of the muscle makes it possible to subdivide the muscle into two functional units for segmental muscle transfer.