There are two possibilities for back pain with frequent urination. First, common urinary tract infection, which manifests as urinary tract irritation symptoms of frequent urination, urgent urination, painful urination, and even hematuria and fever in severe cases. When retrograde infection causes inflammation in the kidneys, there will also be soreness and pain in the lower back. The diagnosis is established by laboratory tests, urine routine or blood routine, which can reveal a significant increase in white blood cells; secondly, urinary stones, when stones attack, they will cause renal colic on the affected side and painful soreness and swelling in the lower back. If the stone is located in the lower part of the ureter or the end of the ureter, near the bladder, there will be symptoms of frequent, urgent and painful urination, which can be clearly diagnosed by CT or urinary ultrasound.