Objective To study the value of the intervention of Nitroglycerin(NTG) on ~(99m)Tc-MIBI myocardial tomography imaging in the estimation of myocardial viability.Method According to the analysis of autologous electrocardiogram(ECG),a total of 66 patients with unstable angina(UA) was divided into group A and group B.The patients in group A were without old myocardial infarction and those of group B were with old myocardial infarction.The patients in the two groups were respectively underwent the resting ~(99m)Tc-MIBI myocardial tomography imaging and the NTG administration intervened the next day.The imaging was collected and tested by the computer.Results Of 594 myocardial segments in the 66 cases,242 segments(40.7%) in testing myocardial imaging were proved to be perfusion abnormal,while after the intervention of NTG administration,the perfusion of 114 segments(47.1%) had been improved according to the imaging.Conclusion The intervention of NTG administration on ~(99m)Tc-MIBI myocardial tomography imaging for myocardial viability is simple,safe,objective and accurate,which provides a forceful means for the post-operative evaluation and the selection of indication before the rebuilding of coronary artery of the UA patients.