Fast heartbeat in the morning may be caused by normal physiological phenomenon, arrhythmia, hyperthyroidism, anemia and other reasons. 1. Normal physiological phenomenon: Getting up in the morning due to sympathetic over-excitement, vagus nerve inhibition may lead to physiological heartbeat. 2. Cardiac arrhythmia: coronary atherosclerosis, myocarditis, heart failure and other diseases may have an impact on the electrical conduction of the heart, and there may be a fast heartbeat in the morning. 3. Hyperthyroidism: when the thyroid gland is hyperfunctional, elevated levels of thyroid hormones can lead to increased metabolic levels and increased sympathetic excitability, which can also lead to symptoms of fast heartbeat in the morning. 4. Anemia: When anemia occurs, the decrease of hemoglobin leads to the decrease of oxygen-carrying capacity, and the symptom of hypoxia of the whole body organs can appear the phenomenon of fast heartbeat in the morning. If the phenomenon of fast heartbeat in the morning, you need to go to the hospital for further examination of electrocardiogram, cardiac ultrasound, blood routine, thyroid function, thyroid ultrasound and other items to find the cause.