Hematuria after catheterization commonly occurs when there is insufficient lubrication during the catheterization process or when there is an abnormal disease in the urethra itself, resulting in damage to the mucosa of the urethra or bladder, resulting in hematuria. This type of bleeding is usually small and can recover and improve on its own with more water and diuresis. It can also be seen in patients who have corresponding lesions in the bladder itself and have hematuria itself, such as kidney disease, bladder tumor, cystitis, nephritis, etc. The catheterized urine is hematuria, which needs to be given timely treatment for the disease, and the hematuria will improve naturally after it is treated. In addition, we should also pay attention to whether the hematuria after catheterization appears when the catheter is removed, if it appears after the catheter is removed, we need to observe whether the situation of hematuria has improved, we can first give active anti-inflammatory, drink water to promote the urine situation, if the hematuria has gradually improved, we can recover. However, if the hematuria is further severe, it may be necessary to insert the catheter again for compression to stop the bleeding.