The middle ear is a part of system of continuous organ including the nose, nasopharynx, eustachian tube, middle ear, and mastoid. Respiratory mucosa is continuous through the system. Thus, sign and effect of inflammation, infection, and obstruction in one area are likely to be reflected in other area. The vast majority of patient with otitis media and related conditions have abnormal function of the eustachian tube that may have caused secondary mucosal disease of middle ear. Nasal obstruction may also be involved in the pathogenesis of otitis media with effusion. The electroacoustic impedance bridge is usually adequate to assess eustachian tube function and middle ear state clinically. The presence of middle ear effusion or high negative middle ear pressure as determined by this method usually indicated impaired eustachian tube function. The authors experienced the 138 patients of nasal obstruction with or without negative middle ear pressure preoperatively. The middle ear pressure was measured with the Teledyne Avionics model TA-4D. The results were follows : 1) The cases of negative middle ear pressure were 70 ears(25%) among the 276 cases of severe nasal obstruction preoperatively. 2) The 15 cases(7.3%) among the 206 cases of nasal obstruction with normal middle ear pressure preoperatively, the 3rd day keeping anterior nasal packing after nasal operation, had decreased middle ear pressure(less than-100 mmH₂O). 3) The 3rd day keeping anterior nasal packing after nasal operation, most common tympanometric type of patients who had nasal and nasopharyngeal problem with normal middle ear pressure was type A(92.7%) but the tympanometric type of patient with decreased middle ear pressure was type C(61%). 4) In the group of normal middle ear pressure preoperatively(206 ears), all cases with transient postoperative deceased middle ear pressure was completely recovered within 2 weeks. 5) The normalization of tympanogram in the cases of normal middle ear pressure preoperatively was faster than the cases of preoperative negative middle ear pressure due to nasal and nasopharyngeal pathology.