Coronary CTA is a non-invasive examination method, which actually scans the coronary arteries by multi-row spiral CT (MDCT for short) to understand the coronary lesions. Since the first 4-row MDCT was introduced in 1998, after the development of 8, 16 and 32 rows, the most advanced MDCT has now reached 512 rows. The “rows” refers to the number of arrays of CT scanner detectors. Generally, the more rows, the wider the detector width, and the greater the width of a completed scan. Recent advances in imaging have shown that noninvasive coronary CTA can clearly show the coronary artery lumen and even know the density of atheromatous plaque. It can show the site and degree of coronary artery stenosis, with sensitivity and specificity of 87.5% and 97.2% for the diagnosis of luminal stenosis, and positive predictive value and negative predictive value of 82.4% and 98.1%, respectively, but it cannot replace coronary angiography yet. The main reason is that CTA of coronary arteries is affected by heart rate and respiratory rate, which increases the chance of artifacts, such as heart rate over 70 beats/min, arrhythmia or heart failure, etc. Reliable images cannot be obtained. The dynamic observation of coronary flow is not as good as coronary angiography; the assessment of restenosis within the coronary stent is limited, etc. Most importantly, coronary CT is only an examination tool, while coronary angiography can simultaneously perform interventional treatment for suitable lesions. Therefore, in short, coronary CT can be chosen for patients who cannot do coronary angiography and are not clinically inclined to coronary artery disease but need to rule out coronary artery disease and evaluate the efficacy after intervention or bypass surgery; while coronary angiography should be preferred for patients with high clinical suspicion of coronary artery disease who are likely to need simultaneous intervention.