Objective To establish a three‑dimensional (3D) model based on Materialise's interactive medical image control systems (MIMICS) for the air leakage of laryngeal mask airway (LMA) during insertion into the pharyngolaryngeal cavity (PLC), and to investigate the morphological changes of LMA and PLC and the gap between them. Methods CT scanning was used to obtain the data of PLC with full filled LMA (PLC‑LMA). Meanwhile, the data of LMA and the normal neck were obtained and then imported into MIMICS to establish a LMA model, a PLC model and a PLC‑LMA model. Results We compared the PLC model with the PLC‑LMA model and found that after LMA insertion, there were changes in shape and position of the hyoid bone and thyroid cartilage as well as the PLC. After LMA insertion, the gap among the pyriform sinus, posterior pharyngeal wall and LMA pharyngeal mask mouth‑pharynx end were potential gas leakage tunnels, which might be the places that the gas leaked by mechanical ventilation flowed out before entery into the oropharynx and nasopharynx. Conclusions The computer‑aided 3D modeling can clearly visualize the displacement and deformation of LMA and PLC before and after insertion of PLC into LMA, which provides further reference for selection of an appropriate size of LMA and improve LMA design.