Foam in urine may be caused by food factors, concentrated urine, urinary tract infection disease, kidney disease, diabetes and other factors. 1. Food factors: consuming a large amount of food containing high protein, such as meat, there may be a small amount of protein into the urine, urination, it will make the presence of foam in the urine, no other clinical symptoms. 2. Concentration of urine: Holding urine for too long may lead to the concentration of urine, and in the process of urination, the impact of urine is larger, it will make the urine foam, but the foam will quickly dissipate. 3. Urinary tract infections: Foam in the urine, and accompanied by obvious urinary abnormalities, such as urinary pain, urinary frequency, urinary urgency, etc., may be caused by urinary tract infections, such as cystitis or urethritis. 4. Kidney disease: urine foam lasts for a long time, and is accompanied by symptoms such as swelling of the lower limbs, may be related to some kidney diseases, such as glomerulonephritis, and in severe cases may also lead to renal failure and other serious complications. 5. Diabetes: diabetes itself, will often appear foamy urine, especially in the elevated blood sugar, foamy urine is more obvious, accompanied by drinking and fatigue and other symptoms, can lead to ketoacidosis in severe cases. Foam in the urine, and accompanied by other abnormalities, should be alert for disease factors, it is recommended to go to the hospital urology department for appropriate examination and treatment.