Lactate dehydrogenase is an enzyme widely present in human body, mainly in cardiac muscle, skeletal muscle, kidney, liver cells, pancreas, etc.. Its elevation is mainly considered for the following reasons: i. Physiological, for example, after strenuous activity can cause elevation of lactate dehydrogenase, mostly related to muscle damage. Second, pathological state, such as myocardial infarction, hepatitis, malignant tumor, pulmonary tethering, kidney disease, progressive muscular atrophy, etc. can cause elevation of lactate dehydrogenase. If the lactate dehydrogenase level of 2000 is significantly higher than the normal range, it is necessary to: i. rule out any errors in the test and retest once. ii. Second, exclude any history of strenuous activities, such as fitness, excessive running, etc. Third, there is no other discomfort, such as chest tightness, chest pain, etc. In other words, it is necessary to combine other medical conditions and auxiliary tests to determine the cause of elevated lactate dehydrogenase and to make a basis for the final diagnosis of the disease.