For patients, it is a pleasure to be able to check their condition easily and painlessly. Coronary CT is undoubtedly an advancement in the diagnostics of coronary artery disease in recent years, because it is a non-invasive test for patients. Patients can detect coronary artery lesions through this test, which is both easier and more economical than coronary angiography, with less pain and less exposure to radiation for both doctors and patients. Since coronary CT has so many advantages, can it completely replace coronary angiography? The answer is no. Coronary CT has its technical bottlenecks. The quality of coronary CT imaging is easily affected by the patient’s cardiac function, heart rate, heart rhythm, respiration and other factors, and is not as clear and accurate as coronary angiography, and the small branches of the coronary arteries cannot be fully displayed, and the dynamic observation of coronary blood flow is not as good as coronary angiography. If the patient’s heart rate exceeds 70 beats/min before the imaging is performed, the clinician should give the patient betalactone orally and wait until the patient’s heart rate is controlled to below 70 beats/min before performing the examination. How should we choose between these two types of examinations? Coronary CT has the advantages of non-invasive, low cost, sensitivity, specificity and accuracy, and can be used as a screening test for the diagnosis of coronary artery disease; while coronary angiography can simultaneously perform interventional treatment for suitable lesions. Therefore, coronary CT can be chosen for patients who cannot do coronary angiography, who are not clinically inclined to coronary artery disease but need to exclude coronary artery disease as well as those who are too afraid of coronary angiography procedures and the evaluation of efficacy after intervention or bypass surgery, while coronary angiography should be preferred for patients who are highly suspected of coronary artery disease clinically and are likely to need interventional treatment at the same time.