The normal value of potassium in blood is 3.5-5.5mmol/L. Below 3.5mmol/L is considered as hypokalemia, which can be supplemented by medication and dietary adjustment. Early pregnancy reactions such as vomiting, diarrhea, etc. can occur during pregnancy, resulting in a large loss of potassium in the body, causing hypokalemia and accompanying symptoms such as lethargy, loss of appetite, constipation, etc. A blood potassium level of 3.38mmol/L is considered low potassium. Blood potassium is 3.38 mmol/L. Low potassium is relatively mild and can be considered as a result of pregnancy vomiting or nutritional imbalance, and can be supplemented by eating more food with higher potassium content such as banana, melon and spinach. If the blood potassium continues to decrease, potassium supplementation drugs such as potassium chloride and potassium citrate should be applied according to medical advice. Pregnant women should eat more food rich in protein during pregnancy, such as eggs, lean pork, soybean products, milk and so on. It is also necessary to properly supplement shrimp, fish, pork liver, oatmeal, walnuts, peanuts and other foods, eat more fresh vegetables and fruits, to ensure that the intake of food nutritional balance, to avoid a single nutrition. During pregnancy, pay attention to more rest, at the same time should relax, avoid tension, anxiety, any discomfort should be timely to the hospital, by the doctor to clarify the diagnosis, and cooperate with the doctor to deal with the symptoms.