The authors analysed the importance and results of tympanometric examination by children in preschool institutions of Kosovska Mitrovica, Zvecan, Zerovnica, Socanica, Leposavic, Lesak and Zubin Potok. Children underwent ENT examination, which included clinical ENT examination and accessory diagnostics methods: tympanometric exami-nation and bacteriological analyses of the nose and throat secret. Totally, it have examined 870 children. The most frequent cause of the middle ear impairment was Eustachian tube dysfunction or "willingness of the middle ear for disease" (50,5% cases). Rarely, it was transient effusion in the middle ear and serous otitis media (19,02%). The authors underline a great importance of tympanometric examination by preschool children in detection of middle ear diseases.