Hemifacial microsomia is the second most common congenital anomaly of the craniofacial region. Hemifacial microsomia is characterised by unilateral hypoplasia of the ear. Treatment of this condition depends on the severity of the lesion. The treatment of hemifacial microsomia must be carried out by a multidisciplinary group of professionals familiar with this pathology, including plastic surgeons, parapsychologists, orthodontists, and paediatricians. In hemifacial microsomia, microtia is usually accompanied by alterations of the middle ear. Since the ear develops embryonically from the first and second branchial arches, the facial areas that also develop from these embryonic origins are usually affected to a greater or lesser degree, including through hypoplasia of the jaw, maxilla, zygomatic bones, and temporal bone, among others. Although jaw hypoplasia is the most evident deformity in craniofacial microsomia, microtia is the alteration that often has the greatest aesthetic impact on patients. Alterations in dentition are also common, typically presenting as a cephalad inclination of the anterior occlusal plane of the maxilla and mandible on the affected side. This study aims to review the surgical approach and evaluate the results of a paediatric case of hemifacial microsomia. Hemifacial microsomia is present at birth, and successful reconstruction is essential for the correct integration of such infantile patients into society. Multiple facial asymmetries as well as neonatal onset are a challenge for reconstructive surgery, and the importance of multidisciplinary treatment in these patients must be emphasised.