Multidetector CT is the best imaging method to diagnose tracheal diverticulum (TD) till now. MRI characteristics of this disease is not reported before. The study report 5 cases of TD, intend to discuss the role of MRI in diagnosing and managing tracheal diverticulum (TD).Five cases of TD (include 4 cases of uninfected TD and 1 case of infected TD) with complete CT and MR imaging data were collected and analyzed to compare MR and CT imaging features(location/size/wall/channel) of the disease. The role of MRI in monitoring therapeutic efficacy of infected TD was also discussed.All cases were located in the right posterolateral region of the trachea at the level between the T1 and T3 vertebrae. MRI was better in showing the wall of TD, and inferior to showing the channel (between TD and the tracheal) than CT. The diameter measured in MR images was longer than measured in CT image. MRI had equal capacity with CT in accurately display the location of the disease. MRI sensitively showed the absorption of infected TD.MRI is helpful in diagnosing TD, especially infected TD. The sign that local thickening and signal increasing of tracheal wall observed on MR images means that a paratracheal abscess may originate from TD. MRI plays an important role in monitoring therapeutic efficacy of infected TD.Copyright © 2021 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.