Microtia is a disorder characterized mainly by hypoplasia of the ear. Most of them are accompanied by atresia of the external auditory canal (no external auditory canal), and some patients are accompanied by narrowing of the external auditory canal. In severe cases, there is no vestige of an auricle in the ear, which is called auricular malformation. Simple auricular reconstruction can be performed after the age of 10, mostly at the age of 13-14, because the material for auricular reconstruction, rib cartilage, is basically enough for reconstruction at that time. After the age of 20, rib cartilage ossifies and becomes less flexible, which may affect the reconstructive effect. Currently, there are two main methods of auricular reconstruction: hydrocapsular expansion and non-hydrocapsular expansion. Each has its own advantages and disadvantages. Whether and when the external auditory canal should be reconstructed depends on the development of the affected ear (temporal bone), the development of the contralateral ear and the hearing. If the development and hearing of the contralateral ear are normal and the affected ear is evaluated to be suitable for external auditory canal reconstruction, the auricle can be reconstructed at the same time, or the auricle can be reconstructed alone. When the external auditory canal is atretic in both ears at the age of 4-6 years, one side of the external auditory canal canal can be reconstructed first, and bone conduction hearing aids can also be implanted as an option. However, patients with external auditory canal stenosis are at risk of complicating external auditory canal cholesteatoma, and should be seen promptly if they develop ear drainage, peri-auricular redness and swelling.