The possible reasons for the increase of foam in urine are as follows: 1, urine concentration state, common in the morning when the first defecation more foam in urine, because the morning urine has been stored in the bladder for a long time, generally > 4 hours or more, so there will be different degrees of concentration, in the process of urination can appear small bubble-like changes. This situation can be improved after drinking more water, and is not a disease condition. 2, proteinuria, when there is a high level of protein in the urine of patients with kidney disease can appear more foam, more small foam, lasting longer, and may be accompanied by abnormal kidney function, edema or reduced urine volume changes, need to further urinary routine, 24-hour urine protein quantification and other tests to determine. 3, internal medicine Diseases, such as diabetes, fever or ketoacidosis, patients with higher solute concentration components in the urine, such as higher urine sugar, higher ketone bodies in the urine or fever itself resulting in concentrated urine can appear increased foam, further urine laboratory tests and related internal medicine examination are needed to confirm the diagnosis.