Urine is brown, the possible causes: 1, old urinary bleeding, can be manifested as urine is brown or soy sauce color, most often seen after trauma, in the healing process, blood stored in the urinary tract after vulcanization, manifested as dark brown or soy sauce color. 2, the presence of more bilirubin in the urine, urine bilirubin, there can be a dark brown or dark yellow urine, accompanied by the whole body skin and mucous membranes yellowish staining, liver function tests appear abnormal liver function and accompanied by elevated serum bilirubin levels, mostly related to liver and biliary system diseases. Liver function tests appear abnormal liver function, and accompanied by elevated serum bilirubin levels, mostly related to liver and biliary system diseases. 3, the urine is extremely concentrated, can appear brown, such as urinary retention patients catheterization can be found after the color of the urine is dark brown, or long time hold the urine of the patient, drinking less water, body temperature rises, water loss, or nausea and vomiting of the patient, can be extremely concentrated, manifested as dark brown urine. The color of the urine is dark brown.