The possible causes of blood at the end of urination are as follows: 1. Posterior urethral infection or bladder neck infection can appear as terminal carnal hematuria, accompanied by symptoms such as urinary frequency, urinary urgency and painful urination. Due to the closure of the urethral sphincter in the end state of urination and the closure of the bladder neck, it can lead to bleeding from the local erosion of the mucosa, which is mixed in the urine and manifests as terminal hematuria, accompanied by painful sensation at the end of urination. Routine urinalysis, urine culture test and urethroscopy are needed to further confirm the diagnosis.2. If there are posterior urethral stones or bladder neck stones, they can also lead to blood at the end of urination and can be accompanied by abnormal urination, such as straining to urinate, bifurcation of urination or interruption of urine flow. Ultrasound examination of the urinary system is needed to further rule out the presence of stones.3. If there is trauma to the posterior urethra, such as a combined pelvic fracture followed by urethral contusion, terminal hematuria can occur, and patients often have a clear history of trauma, which can be accompanied by a feeling of straining to urinate.