High uric acid is mainly caused by two main reasons: increased uric acid production and decreased uric acid excretion, which can only be diagnosed based on the patient’s medical history and relevant tests. Uric acid is the end product of purine metabolism and is mainly produced by the enzymatic breakdown of nucleic acids and other purine compounds from cellular metabolism and purines from food. The saturation and concentration of uric acid in the body at 37°C is about 420 μmol/L (7 mg/dl), and exceeding this concentration is considered hyperuricemia. There are two main causes of high uric acid: increased uric acid production and decreased uric acid excretion, and sometimes both of them coexist. Increased uric acid production: This includes both high purine dietary intake and increased endogenous purine metabolism. Food-induced uric acid production is proportional to the purine content of the food, and purine-rich foods include mainly animal offal and seafood. The increase of endogenous purine metabolism is mainly related to the abnormal synthesis and decomposition of purine. Decreased uric acid excretion: About 2/3 of uric acid is excreted through the kidneys, and the remaining 1/3 is excreted through extrarenal pathways such as the intestinal tract and biliary tract. About 90% of patients with persistent hyperuricemia have a defect in renal processing of uric acid and show reduced uric acid excretion, including reduced glomerular filtration rate, increased tubular reabsorption, reduced tubular secretion and impaired renal function due to urate crystallization. Therefore, it is important to seek timely medical attention to find the specific cause so as not to delay the condition.