Background: Positioning of patients during surgery, whether prone or head down, can lead to airway edema which, in turn, may lead to a difficult airway, and enhanced chances for reintubation. We aimed to assess and evaluate modified Mallampati class (MMC) change in patients scheduled for lumbar spine surgery in the prone position. Materials and Methods: This prospective observational study included 80 patients scheduled for lumbar spine surgery. The MMC was assessed up to 48 h postoperatively. The time taken by the patients in the postoperative period for MMC class to revert to preoperative value and airway complications, if any, was noted. Other parameters observed were surgical duration, intraoperative fluids used, and blood loss to look for any significant correlation with changes in MMC. Results: MMC increase by one grade was observed in 73 patients (91%). MMC in 54 patients (74%) returned to baseline within 18 h, in 12 patients (16%) it took 24 h, and in the remaining 7 patients (10%) the time taken was 36 h. Conclusion: It was concluded and established by this study that the MMC declined by one grade and reverted to baseline value within 36 h. This change in MMC necessitates extra caution to be adopted during the postoperative period as surgery in a prone position may predispose to an increased risk of encountering difficult reintubation. The change in MMC was not significantly correlated to intraoperative variables like duration of surgery, amount of intraoperative fluid given, and blood loss.