The possible reasons for yellow and foamy urine are: first, when the urine is concentrated, the urine discharge will produce more foam with water shock. This is because the concentration of solutes in the concentrated state of urine is too high, so it will produce shocking foam, this situation is not a pathological change, only need to drink more water appropriately; second, if the protein content in the urine is high, the situation of urine foam can appear, the foam is smaller and lasts longer. If there is a large amount of proteinuria, there may also be swelling of the face or limbs and other manifestations, which requires routine urine examination to confirm the diagnosis; third, if suffering from urinary tract infection, there can also be yellow urine, accompanied by increased foam during urination, and may also be accompanied by urinary frequency, urinary urgency, painful urination and other symptoms, which requires routine urine or urine culture examination to confirm the diagnosis; fourth, if there is a high level of urine sugar Or if there is a positive urine bilirubin result, there can also be a yellowish color of urine accompanied by a higher amount of foam.