Foamy urine is usually a normal phenomenon, but may also be due to kidney disease proteinuria. 1. Normal phenomenon: usually the healthy human body is the phenomenon of urine foam, because in addition to water in the urine, there are a lot of waste excreted by the body such as urea, ammonia and uric acid, etc., which can easily lead to the phenomenon of foam in the urine. 2. Proteinuria caused by kidney disease: patients with kidney disease due to glomerular basement membrane damage, resulting in protein into the urine, resulting in proteinuria, which causes the phenomenon of foam in the urine. Foamy urine may have other reasons, patients who find themselves in the urine unexplained foam, should promptly go to the hospital urine routine examination to see whether it is a pathological cause, under the guidance of the doctor’s treatment.