Objective To observe the analgesic effect of ultrasound‑guided iliohypogastric/ilioinguinal nerve (IIIHN) block in elderly patients after photoselective laser vaporization of prostate (PVP). Methods A total of 58 patients, aged 65−80 years old, American Society of Anesthesiologists (ASA) Ⅱ−Ⅲ grade, who underwent PVP surgery in People's Hospital of Xinjiang Uygur Autonomous Region from January 2022 to May 2022 were selected. According to the random number table method, they were divided into two groups: a IIIHN block combined with general anesthesia group (group I, n=28) and a general anesthesia alone group (group G, n=30). Patients in group I underwent ultrasound‑guided bilateral IIIHN block before general anesthesia, and each side was injected with a concentration of 0.5% ropivacaine at a dose of 0.25 ml/kg. Group G received general anesthesia alone. The intraoperative dosages of propofol and remifentanil, and the postoperative dosages of ketorolac tromethamine for rescue analgesia were recorded. The Visual Analogue Scale (VAS) scores were recorded at rest and during exercises at postoperative 1, 6, 12 h and 24 h. Postoperative adverse reactions such as nausea, vomiting, vertigo, drowsiness, pruritus, and complications related to regional block were recorded. Results The VAS scores at rest and during exercise at postoperative 1, 6, 12 h and 24 h in group I were lower than those in group G (P<0.05). There were no significant differences in general information, operation time, intraoperative blood loss, propofol dosage, remifentanil dosage, the use of ketorolac tromethamine for rescue analgesia after surgery, and yje incidence of postoperative adverse reactions between the two groups (P>0.05). No complications related to regional block were found in both group. Conclusions Ultrasound‑guided IIIHN block is safe and effective for postoperative analgesia in elderly patients after PVP, which can relieve patients' early pain at rest and during exercise and accelerate their recovery.