To compare perioperative and functional outcomes between improved (port-free) single-site robot-assisted laparoscopic radical prostatectomy (pf-ssRARP) and standard multi-port robot-assisted radical prostatectomy (MPRARP). A total of 372 consecutive patients underwent RARAP using the da Vinci Si® robotic surgical system. Group I (n = 210) included patients undergoing pf-ssRARP and Group II (n = 162) included patients undergoing MPRARP. Demographics and perioperative data including postoperative recovery outcomes were recorded and compared between the two groups. Overall mean operative time was significantly shorter with the pf-ssRARP compared to the MPRARP (p < 0.05). The length of hospitalization after the pf-ssRARP was shorter (p < 0.05). In Group I, the positive surgical margin rate was 15.2%; while in Group II, the positive margin rate was 33.3% (p < 0.05). The rate of instant urinary continence was significantly higher in Group I than in Group II (p < 0.05). The percentage of urinary continence was higher in the pf-ssRARP than in the MPRARP, at 6 months post-surgery (p < 0.05) and 9 months post-surgery (p < 0.05). There was no significant difference in the proportion of erectile function in the pf-ssRARP and MPRARP groups at the time of reaching the endpoint of this study (p > 0.05). The two groups were comparable in terms of total hospitalization costs (p < 0.05). The improved (port-free) single-site robot-assisted laparoscopic radical prostatectomy is a practical and easy technique to implement in clinical practice. Extraperitoneal implementation of the modified technique requires only a small incision, no special PORT, no additional auxiliary foramen creation, increased postoperative aesthetics and reduced hospitalization costs, and a high percentage of early postoperative urinary control recovery.