Systolic blood pressure of 170 mmHg is serious and can lead to complications if not controlled in time; diastolic blood pressure of 170 mmHg is very serious and may have hypertensive emergencies. Normal systolic blood pressure should be <140mmHg and diastolic blood pressure should be <90mmHg; 3 measurements of systolic blood pressure ≥140mmHg and/or diastolic blood pressure ≥90mmHg on a non-same day are diagnostic of hypertension. If the systolic blood pressure is 170mmHg, the blood pressure should be re-measured twice on non-same day; if it is still higher than normal, hypertension can be diagnosed; systolic blood pressure of 170mmHg belongs to at least grade 2 hypertension, which needs to take antihypertensive medication, such as metoprolol, to control the blood pressure. If the blood pressure is well controlled, the prognosis is good, but those with poor blood pressure control may have cerebral infarction, heart attack and other cardiovascular diseases, and the serious cases may be life-threatening. If the diastolic blood pressure is 170mmHg, it is a very high blood pressure, and if it is accompanied by progressive cardiac, cerebral, renal and other organ insufficiency, it is a hypertensive emergency, and if it is not accompanied by target organ damage, it is a hypertensive sub-emergency. Elevated blood pressure can cause headache, nosebleed, chest tightness and other symptoms. Nitroglycerin should be used in time to reduce blood pressure and prevent target organ damage. It is recommended that patients with systolic blood pressure of 170mmHg should have their blood pressure retested, and those whose retest results are still abnormal should consult a doctor in time, and patients with diastolic blood pressure of 170mmHg should consult a doctor as soon as possible to prevent aggravation of their condition.