Chest pain is one of the common clinical symptoms with complex and diverse manifestations and widely varying clinical risk. Therefore, the diagnosis and differential diagnosis of chest pain should take into account the medical history, physical examination, ECG and initial cardiac marker results to make a rapid and rough assessment of the possible causes and risks of chest pain. Sclerotic disease is the “gold standard”. We should not only pay attention to the common ischemic chest pain and the non-ischemic chest pain of cardiac origin that can also be life-threatening, such as aortic coarctation and pulmonary embolism, but also eliminate patients with low-risk chest pain to reduce unnecessary waste of medical resources. The etiology of chest pain can be broadly divided into cardiac and non-cardiac diseases, and cardiac diseases are further divided into cardiac ischemic diseases and cardiac non-ischemic diseases, the former including chronic stable angina pectoris (SA) and acute coronary syndrome (ACS). Obviously, the ancillary tests required for chest pain of different etiologies should be different, and even cardiogenic ischemic diseases should be treated differently according to different risk states. Those with chest pain caused by non-cardiogenic diseases do not require aggressive coronary angiography, and other causes of symptoms such as respiratory diseases (pulmonary embolism, pneumonia, pneumothorax, etc.), gastrointestinal diseases (e.g. esophageal spasm, gastritis, peptic ulcer or cholecystitis, etc.), skeletal muscle disorders and psychiatric disorders (anxiety, hyperventilation, etc.). Non-ischemic diseases of cardiac origin such as aortic coarctation, valvular pericardial disease or cardiac insufficiency can be clearly diagnosed by noninvasive examinations such as echocardiography and MRI, and do not require aggressive coronary angiography. The decision of whether to perform coronary angiography cannot be based on resting ECG abnormalities alone, especially if no further chest pain occurs during the observation period and the ECG and cardiac markers are dynamically observed to be normal, early stress test (exercise test or drug loading nuclear myocardial perfusion imaging) can be considered, and coronary angiography can be considered if the stress test is positive. Should coronary angiography be actively performed in all patients with clinically confirmed coronary artery disease? Aggressive coronary angiography is not recommended in patients with stable angina who are unwilling to undergo revascularization therapy, or in patients with CCS class I or II angina who are effectively treated with medication and have no evidence of ischemia on noninvasive testing; in patients with CCS class I or II angina who have good left ventricular function and insufficient high-risk criteria on noninvasive testing, CCS class III or IV who have reached class I or II with medication, CCS class I or IV, and CCS class I or IV who have reached class I or II with medication. II, SA with CCS grade I or II angina but not tolerating drug therapy, whether coronary angiography is performed needs further observation; if severe angina (CCS grade III and IV) is still present despite drug therapy and noninvasive examination shows high risk (severe left ventricular dysfunction: EF < 0.35, large anterior wall or multiple filling defects, sudden cardiac death or severe ventricular arrhythmia surviving Patients with angina pectoris, angina pectoris with congestive heart failure, clinical features suggesting the possibility of severe coronary artery disease, severe left ventricular insufficiency, and SA with insufficient information to determine prognosis by noninvasive examination are advocated to actively perform coronary angiography to clarify the diagnosis and understand the extent of lesions, so as to lay the foundation for active hemodynamic reconstruction therapy. In low-risk unstable angina (UA) with myocardial ischemia induced by exercise above Bruce class III or 6 metabolic equivalents after 1 week of stabilization, active coronary angiography is not necessary. If the amount of activity below the above induces angina as well as those with UA at intermediate or high risk, coronary angiography should be performed if conditions allow. Those with non-ST-segment elevation myocardial infarction (NSTEMI) without comorbidities, hemodynamic stability, and without recurrent ischemic episodes may be considered for elective coronary angiography and treatment. Intermediate and high risk NSTEMI should be treated with urgent coronary angiography and intervention. UA/NSTEMI with recurrent myocardial ischemia despite adequate drug therapy, high risk clinical presentation (congestive heart failure, malignant ventricular arrhythmias), or high risk on noninvasive testing, and previous mechanical revascularization should be considered for urgent coronary angiography and intervention. Patients with acute myocardial infarction (STEMI) with ST-segment elevation and new left bundle branch block who still have significant chest pain after thrombolytic therapy and clinical indications of non recanalization should undergo emergency coronary angiography as soon as possible. If there is no ischemic recurrence, elective coronary angiography should be performed 7-10 days after thrombolytic therapy for recanalization. Those with STEMI who have contraindications to thrombolysis but are suitable for reperfusion should undergo direct coronary angiography and interventional intervention. A clinic with a suitable catheterization laboratory and experienced operators should perform direct coronary angiography and intervention in STEMI 3-12 hours after the onset. Direct coronary angiography and intervention are preferred for STEMI with cardiogenic shock and age <75 years, onset within 36 hours, and hemodialysis that can be completed within 18 hours of shock onset. In conclusion, for each patient with chest pain, we should make full use of clinical history, physical examination, and noninvasive examination to make good diagnosis and differential diagnosis. If coronary angiography is used as electrocardiogram, which is disfavored by cardiologists, and the failure to correctly and reasonably grasp the indications for coronary angiography is undoubtedly the sadness of contemporary cardiologists.