High urine specific gravity may be physiological reasons and pathological reasons, such as urinary tract infection, kidney disease, etc. In addition, patients with diabetes may also have elevated urine specific gravity. 1. Physiological reasons: most often seen in too little water or sweating more, there is a concentrated state of urine, there can be an increase in specific gravity, accompanied by yellowish urine color and other changes. 2. Pathologic causes (1) Urinary tract infection: when there is a urinary tract infection, the urine contains more white blood cells, pus cells and their proteins, which may cause high urine specific gravity. (2) Renal diseases: such as glomerulonephritis, nephrotic syndrome, and oliguric phase of epidemic hemorrhagic fever. Due to infection or immunity, the glomerular filtration barrier of the kidneys is abnormal, which leads to the entry of proteins into the urine; insufficient perfusion of renal blood flow and so on will lead to high urine specific gravity. In addition, patients with diabetes mellitus may also have an elevated urine specific gravity. When the urine specific gravity is high, it is recommended to consult a doctor in a regular hospital in a timely manner, follow the doctor’s instructions for further examination, clarify the cause with the help of the doctor, and carry out targeted treatment.