An angiography-based spasm provocation test is an accurate diagnostic test of coronary vasospastic angina, but is associated with high patient morbidity, mainly because of the femoral approach and the need for a temporary pacemaker. The purpose of this study was to investigate the safety and feasibility of a transradial ergonovine spasm provocation test. The test was performed prospectively in 174 consecutive patients who were under suspicion of coronary vasospasm at our institution from April 2002 to June 2003. Seventy-eight out of 174 procedures (45%) were performed in an outpatient department. The procedural success rate was 168/174 (96%). All failures were because of access failures, and no major complications were noted. Minor complications were observed in nine patients (severe bradycardia in three, hypotension in two, both in two, and nonsustained ventricular tachycardia in two). The incidence of complications was higher in patients showing prolonged spasm in the right coronary artery. No major local complication was noted other than rebleeding in the puncture site during hemostasis in one patient. The transradial spasm provocation test performed without using a temporary pacemaker may be feasible and safe, with a high success rate and low complication rate as well as low patient morbidity.