Objective: To investigate the relationship between the Apnea Hypopnea Index (AHI) and upper airway examination findings of habitual snorers and obstructive sleep apnea (OSA) patients. Materials and Methods: This study included 264 patients whose tonsils were evaluated in 4 grades. The Mallampati classification was used to determine the relationship between tongue and palate. All patients performed the Müller maneuver in a sitting position. The Fujita classification was used to define the type of obstruction. All patients had polysomnography and were divided into 4 groups according to AHI. Statistical analysis was performed to evaluate the relationship between examination findings and AHI. Results: Of the patients, 133 (50.4%) were habitual snorers, 66 (25%) were mild OSA, 40 (15.2%) were moderate OSA and 25 (9.5%) were severe OSA patients. There was a positive correlation between neck circumference, BMI and AHI in males (p < 0.001). There was a significant difference between patient groups according to Mallampati classification, collapse at the velopharyngeal level and hypopharyngeal level and Fujita classification (all p < 0.001). There were significant relationships between tonsil size, Fujita classification, Mallampati classification, collapse ratios and AHI. Conclusion: We saw that hypopharyngeal area often contributes to obstruction and some examination methods correlate more with AHI. This can aid sleep physicians in the evaluation of OSA patients.