Although useful procedures for radial artery harvest have been reported, forearm circulation and collateral perfusion after radial artery harvesting remain unknown. To assess an optimal radial artery harvest technique for forearm circulation, we designed a prospective randomized trial. Ninety patients were divided into 3 groups of 30 patients. Electrocautery, an ultrasonic scalpel, or sharp scissors and hemoclips were used to harvest radial arteries in groups 1, 2, and 3, respectively. The incidences of harvest site pain, numbness, swelling, discomfort, hematoma, and infection were compared. With forearm thermography, recovery times from cooled down 5 degrees back to rest temperature were compared between groups. All patients had postoperative forearm angiography at 1 and 12 months. Although there were no differences in the incidences of pain, swelling, and discomfort, the incidence of numbness was significantly lower in group 3 (P = .003). The temperature recovery time was significantly shorter in group 3 (P = .0009). On postoperative angiography at 1 month, the incidence of the development of interosseous arteries was significantly higher in group 3 (86.7%) than in groups 1 (23.3%) and 2 (36.7%). The 12-month study, however, showed that there was no difference among groups (73.3%, 80.0%, and 93.3% in groups 1, 2, and 3, respectively). These results suggest that sharp dissection with scissors and clips may be better for early postharvest forearm circulation and can decrease the incidence of hand numbness. However, there were no differences among the 3 methods with respect to forearm circulation 12 months after radial artery harvest.