Abstract: Objective · To evaluate clinical anesthetic effects of nalmefene hydrochloride in pediatric laryngeal mask anesthesia. Methods · Sixty pediatric patients who underwent short-time eye surgeries were randomly divided into nalmefene hydrochloride group (Group N) and the control group (Group C), 30 patients each group. At the end of the surgeries, patients of Group N and Group C were respectively given nalmefene hydrochloride at 0.25 μg/kg and 0.9% sodium chloride at the same volume intravenously. The situation of the patients’ respiration recovery was recorded 1, 2, 3, 4 and 5 minutes after administration, including the time on which the patients’ respiration was recovered and their laryngeal masks were removed. The sedation scores (Ramsay scores) and the incidence of adverse postoperative responses were recorded after the removal of the laryngeal mask. Results · The 5-minute respiration recovery rate was high in Group N, where the 3-minute respiration recovery rate was 83.0%, while only 16.7% in Group C. Besides, respiration recovery time [(3.17±0.78) min] and time for removing laryngeal mask [(4.10±0.95) min] in Group N were shorter than those of Group C (both P<0.05). No significant difference was found in postoperative sedation scores between these two groups (P>0.05). After removing laryngeal mask, the incidence of adverse responses was lower in Group N than that in Group C (P<0.05). Conclusion · Nalmefene hydrochloride is effective in shortening respiration recovery time and laryngeal masks removing time, but makes no difference in patients’ sedative effects, with lower incidence of adverse postoperative respiratory responses.