Abstract: Objective Toexplore the clinical value of diagnosis in coronary artery stenosis degree by exercise gatedmyocardial perfusion imaging (GMPI). Methods Clinical data about 43 consecutive patients with suspectedCAD were retrospectively analyzed.All patients hadunderwent exercise-rest GMPI and coronary angiography (CAG) toverify coronary artery stenosis at left anterior descending (LAD)≥50% on ly. Coronary artery stenosis was dividedintomild, moderate, and serious stenosis. Myocardial perfusion imaging score (MPIS) was obtainedby adding the scores of segments allocatedtothe LAD on exercise-GMPI using a four-point scoring system. The regional wall motion score index (RWMSI) was obtainedon stress GMPI according tothe fourpoint score system. Results The heavier the degree of stenosis was, the higher the RWMSI and MPIS were. The best thresholds of RWMSI and MPIS were acquiredby ROC curve, the RWMSI and MPIS were combinedtodiagnose coronary artery stenosis degree and the results with CAG were compared. The sensitivity and specificity were 41.7% and 74.2% at mildstenosis, 58.3% and 77.4%at moderate stenosis, 66.6% and 80.6% at serious stenosis. Conclusion The combination of RWMSI and MPIS works better in diagnosing serious coronary artery stenosis than mildand moderate coronary artery stenosis.