Coronary angiography is a minimally invasive ancillary test used to examine the coronary vessels for stenotic lesions. It can clarify the location, degree and extent of anatomical abnormalities and obstructive lesions in the coronary arteries. Coronary angiography is currently the only diagnostic method that can directly observe the morphology of coronary arteries, and is the gold standard for the diagnosis of coronary artery disease! Also coronary angiography can be directly followed by treatment for stenosis and obstructive lesions. Coronary angiography can be considered for typical angina symptoms, severe arrhythmias, heart failure and heart enlargement that can withstand imaging, and unexplained chest pain and tightness that cannot be clarified by other diagnoses, etc. Its safety is more ideal, and it is safe and effective for the overall population situation after screening by experienced doctors.