Second-generation supraglottic airway devices (SGAs) are pivotal in airway management, with the ability to accommodate gastric tube (GT) insertion. However, research on GT insertion with SGAs under controlled conditions is limited. This study aimed to evaluate the GT insertion performance of SGAs using a manikin. This prospective study included 32 anesthesiologists in our department, each with more than two years of clinical experience. These anesthesiologists randomly inserted four second-generation SGAs, including i-gel (Intersurgical Ltd., Berkshire, UK), Ambu AuraGain (Ambu, Copenhagen, Denmark), LMA ProSeal (Teleflex Medical, Wayne, PA), and LMA Supreme(Teleflex Medical), all of size 4, into a manikin, followed by GT insertion using Salem Sump™ tubes (Cardinal Health, Dublin, OH) (12 Fr for i-geland 14 Fr for others) until the GT was 55 cm deep at the port entrance. The primary outcome was the difference in GT insertion time, with participants' evaluations. The usual use of second-generation SGAs, including GT insertion, was also surveyed. The differences in GT insertion time among the four SGAs were analyzed using the Friedman test, followed by the Bonferroni method for post-hoc analysis. P < 0.05 was considered significant. The median GT insertion times were 17.2 seconds for i-gel, 9.9 seconds for AuraGain, 18.8 seconds for ProSeal, and 8.9 seconds for Supreme. These times showed significant differences (p < 0.001). Post-hoc analysis revealed that both Supreme and AuraGain had significantly shorter insertion times than i-gel and ProSeal, respectively (p < 0.001). Of the participants, 59% (19/32) evaluated Supreme as the easiest SGA for GT insertion, which is consistent with the observed insertion times. i-gel was the most frequently used SGA, chosen by 72% (23/32) of participants. Additionally, 72% (23/32) of anesthesiologists inserted GTs less than half as often following second-generation SGA placement. Significant differences in GT insertion performance were found among the four second-generation SGAs. According to a survey of participants, second-generation SGAs were often used without GT insertion. Although the differences between products may not be clinically significant, selecting an SGA with easy GT insertion may improve the efficiency and reliability of gastric contentdrainage and enhance the safety of airway management when using SGAs.