Possible causes of frequent urination, but normal urine routine tests: 1. Overactive bladder syndrome, not caused by infections such as bacteria, but due to too frequent contractions of the bladder’s detrusor muscle. When a certain amount of urine is stored in the bladder, the muscles of the bladder become unstoppable and contract. At this point, the patient experiences a distinct urge to urinate and needs to urinate urgently. However, there are usually no symptoms of the urination period and no symptoms such as painful urination, burning sensation in the urethra, or pain in the suprapubic bladder area or back pain. At this time, the urinalysis is completely normal and is only a functional change. The treatment does not require anti-infection treatment, but requires the use of drugs that inhibit bladder contraction, or drugs that reduce bladder sensitivity to treat and improve symptoms.2. There are irritating factors in the urinary system, the possible causes of which are stones or tumors, inflammation and other irritating factors, or the presence of chronic inflammation after the inflammation has healed. When irritating factors exist, frequent urination can occur due to irritation of the bladder mucosa, or strong urination due to continuous bladder contraction, and symptoms of frequent urination can occur.