Transurethral dilation of the prostate (TUDP) with a spherical balloon catheter is a traditional treatment for patients with benign prostatic hyperplasia (BPH). TUDP, however, has been abandoned in clinical application because of its unsatisfying treatment benefit and severe complications. In this study, we redesigned an improved TUDP surgical procedure-transurethral split of the prostate (TUSP)-by replacing the spherical balloon with a columnar balloon. To evaluate the clinical therapeutic effect, we compared the lower urinary tract symptoms (LUTS) of patients with BPH after TUSP treatment and analyzed the urethra through CT films. Animal experiments were performed on aged dogs to investigate the urine function and electromyography (EMG) changes. Histopathology was used to evaluate the inflammation and injury. In addition, collagen content was detected by Trichrome Masson. TUSP attenuated LUTS and reconstructed the urethra in patients with BPH. The attenuation of LUTS was reflected in terms of LUTS parameters such as peak urine flow rate, postvoid residual urine volume, quality of life score, and International Prostate Symptom Score. TUSP expanded the urethra in experimental dogs by splitting the prostate tissues and decreasing the collagen content, with maintenance of normal urinary function and EMG characteristics. The successful clinical application of TUSP with significant therapeutic effect and limited complications made TUSP an ideal choice for the patients with BPH.