Background: Patients under cardiopulmonary resuscitation (CPR) are at high risk of aspirating gastric contents. Nasogastric tube insertion (NGTI) after tracheal intubation is usually performed blindly. This sometimes causes laryngopharyngeal mucosal injury (LPMI), leading to severe bleeding. This study clarified the incidence of LPMI due to blind NGTI during CPR. Methods: We retrospectively analyzed 84 patients presenting with cardiopulmonary arrest on arrival, categorized them into a Smooth group (Smooth; blind NGTI was possible within 2 min), and Difficult group (blind NGTI was not possible), and consequently performed video laryngoscope-assisted NGTI. The laryngopharyngeal mucosal condition was recorded using video laryngoscope. Success rates and insertion time for the Smooth group were calculated. Insertion number and LPMI scores were compared between the groups. Each regression line of outcome measurements was obtained using simple regression analysis. We also analyzed the causes of the Difficult group, using recorded video laryngoscope-assisted videos. Results: The success rate was 78.6% (66/84). NGTI time was 48.8 ± 4.0 s in the Smooth group. Insertion number and injury scores in the Smooth group were significantly lower than those in the Difficult group. The severity of LPMI increased with NGT insertion time and insertion number. Conclusions: Whenever blind NGTI is difficult, switching to other methods is essential to prevent unnecessary persistence.