Objective: The aim of this study was to evaluate the relationship between chronic nasal obstruction caused by nasal septal deviation and Eustachian tube dysfunction–related symptoms using the Eustachian Tube Dysfunction Questionnaire (ETDQ-7) as an assessment in compared study with Tympanometry Eustachian tube function tests result. Methods: This study was carried out at a private clinic in BAGHDAD from May 2018 to February 2019A total of 80 adults were enrolled and divided into 2 groups matched by age and sex. Group 1 (cases) 40 patient (24 male 16 female) age from (18 to 60), with complaint of unilateral or bilateral chronic nasal obstruction due to septal deviation. Group 2 (controls) were healthy adults without any clinical signs or history of persistent nasal obstruction or others nasal problems. The ETDQ-7 scores, ETF tests and Tympanometry results of both groups were compared. Results: In group 1 the median total score of the ETDQ-7was ((2.8) which are Significant higher than in group 2 (1.0)in group 1 (80 ears) 60 had type A, 20 had Type C in Tympanometry results and 30 had Poor ETF test, 10 had Good EDF Test results. In group 2 (80 ears) 72 had type A, 8 had type C tympanogram results and 22 had Poor ETF test, 18 had Good ETF. Conclusion: Patients with nasal obstruction due to DNS had significantly more symptoms related to ETD compared to the healthy controls as subjective data which shown a great association with the results of objective data (Tympanometry and ETF tests). Recommendations 1. We prefer to increase the awareness of otolaryngologist doctor to relationship between septal deviation and Eustachian tube dysfunction. 2. We recommend to do further studies on this subject by make relationship of types of Septal deviation and Eustachian tube dysfunction, as there's new septal deviation Classifications and match every type of septal deviation with Eustachian tube dysfunction