There are more reasons for bubbles in urine, mainly for the following reasons: 1, urine concentration, mostly in the morning urine and drinking too little water, due to the reduction of water in the urine, the solute concentration in the urine increases, can cause bubbles in the urine, which is a normal phenomenon, the symptoms can be quickly relieved after drinking more water. 2, urination after sex can appear bubbles, mainly semen residue in the urethra, semen contains a lot of protein-like substances, can cause bubbles in urine. 3, protein urine, mainly seen in patients with renal impairment, such as diabetic nephropathy, nephrotic syndrome, etc., urine contains a large amount of protein, will cause a large number of bubbles with urine. If there are bubbles in the urine for a long time, you need to go to the hospital to clarify the cause.