Introduction: Eustachian tube is often involved in the pathological processes of the nasal, paranasal, and nasopharynx cavities; therefore, nasal obstruction can alter Eustachian tube function (ETF). The pathogenesis of otitis media has been related to the presence of previous or concurrent nasal diseases. Objective: to study whether there are changes in middle ear pressure after sinonasal surgery. Materials and methods: 59 patients who had different nasal pathologies were subjected to History taking, Clinical examination and Tympanometry. ETF tests in the form of valsalva, Toynbee maneuvers and tympanometry had been performed the day before the operation and after 6 weeks. The postoperative middle ear pressure levels were determined using tympanometry. The middle ear pressure values obtained before and after surgery were compared to determine if there is a statistically significant result. Results: There were a significant improvement of nasal obstruction, ear fullness and tinnitus after surgery. The relation between the middle ear pressure preoperatively and at 6 weeks after removal of nasal packs showed a significant improvement in middle ear pressure (P < 0.05) in both ears. Conclusions: Sino-nasal surgery has a favorable effect on the middle ear pressure and Eustachian tube function.