 Difficult intubation is considered one of the most important obstacle increasing mortality in anesthesiology. Airway assessment tests are proceeded to overcome these difficulties in the pre-anesthetic evaluation. In this study, the Simplified Predictive Intubation Difficulty Score SPIDS and Thyromental Height Measurement TMH were chosen as primary methods to predict difficult intubation. Total 155 ear-nose-throat ENT and Plastic Surgery patients were planned to enroll this study to assess the effectiveness of these tests in predicting difficult intubation in 155 in Maltepe University Hospital and Sisli Hamidiye Etfal Governmental Hospital. 