Background: No previous study investigated the relationship between diferent stages and duration of nasal polypo‑ sis (NP) and Eustachian tube (ET) functions. Thus, the aim of the current study was to assess the relationship between the NP and ET functions by studying diferent staging and duration of the NP. The study included adult patients with bilateral NP. The tridimensional endoscopic staging of the NP was performed to provide information on the location of the NP within the nasal cavity in the three dimensions; horizontal, vertical, and anteroposterior planes. Tympa‑ nometry was performed 1 day before endoscopic staging, and the tympanometric results were distinguished into 3 grades; type A, normal curve; type C; and type B. Results: Within 40 patients (80 nasal cavities, 80 ears), tympanometry showed type A curve in 48 ears (60%), type B curve in 14 ears (17.5%), and type C in 18 ears (22.5%). So, NP was associated with 40% ET afection with non‑signif‑ cant diferences with diferent NP stages at the horizontal plan (P=0.989567), at the vertical plan (P=0.666), and at the anteroposterior plane (P=0.628). While ET afection (ET dysfunction or OME) was reported signifcantly more with NP of longer duration (P<0.0001). Conclusion: NP is associated with a high ET dysfunction rate that is signifcantly higher with NP of longer duration, while diferent NP stages did not signifcantly difer in afecting the ET function