Background: Heart rate recovery (HRR) immediately after exercise is a function of vagal reactivation. HRR following exercise have been demonstrated to be an independent predictor of cardiovascular risk. But there are little data on its prognostic value for angiographic severity of coronary artery disease (CAD). Objectives: We evaluated the relationship between HRR after treadmill exercise test and angiographic severity of CAD in patients with ischemic heart disease. Methods: We enrolled 62 patients (male 34, 55.3짹9.3 years) who underwent both treadmill test and coronary angiogram for suspected CAD between November 2004 and March 2005. HRR was defined as the change from peak heart rate to that measured 2 minutes later. Abnormal HRR was defined as slower recovery than 42 beats per 2 minutes. Results: 13 (62%) of the 21 patients who had abnormal HRR and 13 (31 %) of the 41 patients who had normal HRR had angiographic CAD. The incidence of angiographic CAD is significantly higher in abnormal HRR group (p=0.022). ST segment depression (���1mm) was presented in 21 patients (51 %) of normal HRR group, and 16 patients (76 %) of abnormal HRR group (p=0.51). Conclusion: A delayed decrease of in the heart rate during the second minutes after treadmill exercise, which may be reflection of the angiographic severity of coronary artery disease.