A urinary ketone body (+) found in a physical examination is not a serious condition and may be caused by drinking less water and eating irregularly in the recent phase. Urinary ketone bodies (+) are a sign of elevated ketone bodies in the body, most commonly seen in ketosis in diabetes, and in some patients who have vomiting, diarrhea, do not want to eat, or are on a diet. When the body is hungry, ketone bodies can replace glucose to supply energy to surrounding tissues. If the body does not produce enough insulin, ketone bodies will be produced and the body cannot control the production of ketone bodies. If ketone bodies are elevated in the body, they are elevated in the plasma and will be filtered out of the body through the blood and glomeruli, which is manifested as elevated ketone bodies in the urine. The treatment is to actively look for the cause. If the urinary ketone bodies (+) are simply due to hunger, little food and little water, drink more water and eat more food and the ketone bodies will disappear. If the ketosis is due to diabetes, aggressive blood sugar control is needed.