The radial artery cannulation is often associated with damped arterial waveforms with the hand moving. We used cannulation of the dorsal branch of the radial artery (DRA) and compared the stability of measurement, safety and complications with those of the radial artery(RA).The study was a prospective single-blinded comparative study. Seventy-six patients undergoing general anesthesia requiring arterial cannulation were included. Patients were divided randomly into two separate groups of 35 patients each according to cannulation site: the radial artery (RA group) or the dorsal branch of the radial artery (DRA group). After induction of general anesthesia, cannulation was performed. Three hours after the successful cannulation, the changes of waveforms were noted with the hand moving. We examined whether there were any complications around the cannulation site after cannula removal.With the wrist flexion at all angles (30, 60 and 90 degrees), the frequency of worsening of arterial waveforms was significantly higher in RA group compared with DRA group. Some difficulties in catheter placement were observed in DRA group. No concomitant complication was noticed.Arterial line monitoring from DRA had better waveforms compared with RA monitoring without any complications.