Foamy urine in 8-year-old girls may be caused by drinking too little water, nephrotic syndrome, urinary tract infection and other reasons. 1. Drinking too little water: If an 8-year-old girl drinks too little water in her normal life, resulting in the concentration of urine leading to an increase in the specific gravity of urine, there may be foamy urine, which usually occurs occasionally. 2. nephrotic syndrome: if the 8-year-old girl suffers from nephrotic syndrome, there will be a lot of proteinuria, which may lead to foamy urine. 3. urinary tract infection: if the 8-year-old girl does not pay attention to local hygiene, may cause urinary tract infection inflammation, resulting in the appearance of foamy urine, and at the same time may be accompanied by pain in urination, urinary urgency and other symptoms. 8-year-old girl with foamy urine, there may be other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment or treatment.