Whether or not renal pelvis dilatation can be cured by itself needs to be judged according to the actual cause. If the patient is due to excessive holding of urine before the examination, it can be self-cured, if it is due to urethral stone or other diseases, it usually cannot be self-cured. Dilatation of the renal pelvis is a clinical urologic imaging finding that is usually due to hydronephrosis. There are many causes of hydronephrosis, and the more common clinical cause is mild hydronephrosis due to overfilling of the bladder and increased pressure in the renal pelvis caused by excessive holding of urine prior to the examination. The anterior and posterior diameters of the renal pelvis dilated due to this reason are generally within 10mm, in which case the patient does not need any special treatment and can recover on his/her own after urination. In addition to the above reasons, there are many other diseases such as urethral stones, urethral stenosis, prostatic hyperplasia and so on, which can cause patients to have difficulty in urination, and some of these diseases can also cause patients to return urine from the urethra to the renal pelvis, which can indicate renal pelvic dilatation in the examination. Dilatation of the renal pelvis caused by diseases usually cannot be cured on its own. It is recommended that patients whose tests indicate renal pelvis dilatation should consult a doctor promptly.