Background: Anal surgeries are painful procedures despite advancements in postoperative pain management. Efficient post-surgical pain control is essential to patients' recovery, it may contribute to fastening healing, patient mobilization, and reducing hospital stays. We aimed to evaluate the effect of single-dose gabapentin on postoperative pain in patients who underwent ambulatory anal surgeries. Methods: Prospective, randomized, double-blind controlled study; 50 patients were divided into two equal groups. All patients underwent ambulatory anal surgeries under spinal anesthesia with a plan to be discharged on the same day. Group G received 600 mg of oral gabapentin one hour before surgery, while group C received an oral placebo tablet one hour before surgery. The primary outcome was the severity of postoperative pain (visual analog scale 0 to 10 cm) was conducted at 0, 6, and 12h. The time for the first analgesic request, frequency of rescue analgesia in the first 12 hours, and postoperative sedation (Ramsay sedation score) at 0, 6, and 12h were monitored as secondary outcomes.  Results: The gabapentin group (G) showed significantly lower visual analog scale scores at 6, and 12 in comparison to the control group (C), and group G also showed a longer duration of analgesia and delayed analgesic rescue when compared with the control group. Ramsay sedation score showed insignificant differences between the two groups at 0, 6, and 12h postoperatively. Conclusions: A single preoperative gabapentin dose was effective in decreasing postoperative pain, prolonging the duration of analgesia, and decreasing the total opioid consumption, with no significant complications.