There are many bubbles inside the urine, possible causes: First, the urine contains more protein, which will result in more urine bubbles, more small bubbles and longer duration. A routine urine test, or a quantitative urine protein test is needed to further determine the presence of proteinuria. Secondly, if the sugar content in the urine is increased, more bubbles may appear. Patients can also be accompanied by wasting or increased urine volume, and need to undergo blood glucose testing, urine routine, and urine sugar testing to confirm the diagnosis. Third, if there is urinary tract infection, urine contains more bacteria, pus and other components, more foam can appear when urinating, accompanied by frequent urination, urinary urgency, painful urination or burning sensation in the urethra and other symptoms, it is necessary to conduct routine urine tests to confirm the diagnosis. Fourth, when there is extreme concentration of urine, there can be yellowish urine, increased solute concentration, and many small bubbles visible during urination. It is not accompanied by urinary tract irritation symptoms, and the foam disappears after drinking more water appropriately. The foam due to concentrated urine is larger, and it lasts for a shorter period of time, and can soon dissipate on its own.