Background <p>Laryngeal mask airway malposition during ophthalmic procedures is difficult to detect and poses a significant risk to participant safety, which might cause gastric insufflation, regurgitation, and even pulmonary aspiration during positive-pressure ventilation. Here, we invented a device which would provide another fixation point for the laryngeal mask airway and hypothesized that this new device would improve the stability of the laryngeal mask airway during general anesthesia in pediatric ophthalmic procedures.</p> Methods <p>80 ASA physical status 1–2 participants, scheduled for ophthalmic procedures, were randomly allocated to have the laryngeal mask airway fixed with the new device (Group D, <i>n</i> = 40) or not (Group S, <i>n</i> = 40). The primary outcome was the fiber-optic grades of the laryngeal mask airway position, and the assessors who classified the grades of the fiber-optic photos and analyzed the data were blinded to the group allocation.</p> Results <p>No difference was observed in fiber-optic grades between the two groups before procedures, but the rate of malposition was higher in Group S (10/40 [25%]) than in Group D (2/40 [5%]); absolute difference 20% (95%CI 4.2–35.6%), <i>P</i> = 0.012.</p> Conclusion <p>In conclusion, the new device can effectively improve the stability of the laryngeal mask airway in pediatric ophthalmic procedures&#xa0;performed under general anesthesia.</p> <p>Clinical Trials Registry–China (CTRC) (reference number ChiCTR2200066089). Date of Registration：2022-11-24. URL: <a href="https://www.chictr.org.cn/bin/project/edit?pid=185748">https://www.chictr.org.cn/bin/project/edit?pid=185748</a>.</p>