Introduction: hypertrophied adenoid tissue is one of the most common health problems that occurs in childhood that results in many symptoms including 1. Nasal obstruction. 2. Mucoid, mucopurulent nasal discharge and postnasal discharge 3. Snoring and obstructive sleep apnea. 4. Recurrent acute otitis media (A.O.M). Objective: to evaluate the correlation between subjective and linear measurements of palatal airway on lateral cephalographs. Patients and Methods: Diagnostic lateral cephalometric imaging study that took place from March 2017, to July 2018. 200 Children with chronic mouth breathing (116 boys and 84 girls), with age range from 2 to 14 years, were enrolled in this study. Patients were grouped into three groups according to age: a- 2 - <6 years were 84 patients (42%). b- 6 - <10 years were 76 patients (38%). c- 10 – 14 years were 40 patients (20 %). Results: The age was inversely correlated with the grade of airway obstruction. The correlations between the palatal airway grading with the shortest adenoid distance (SAD) and the most convex adenoid distance (CAD) were r= -0.826 and r= -0.424, respectively, which is statistically significant. The relation between SAD and CAD was directly proportional to each other accounting for correspondence of evaluation in more than 50% of the population which is statistically significant. Conclusion: subjective grading of palatal airway obstruction correlates with the objective measurements of SAD and CAD. Although both methods are reliable in measurement particularly the more severe obstructions, SAD is a more favorable objective tool.