Venous malformations are frequently localized in the head and neck region. However, a cervical localization with an endocranial extension is rather a very uncommon occurrence. We present a case of a 4-year-old child who presented with a large posterior cervical mass evolving for a year, firm and painful at palpation. Imaging was required, revealing a posterior cervical mass with an extension to adjacent structures, a destruction of the occipital bone and an endocranial extension. A macrobiopsy of the mass showed numerous irregular vessels. A surgical treatment was performed due to the extension of the mass, the esthetic prejudice it caused and the uncertain diagnosis. Venous malformation diagnosis was confirmed by a histological examination of the resected piece. Surgical management was not associated with the mass recurrence in our case. Here, we aim at identifying the clinical and radiological features of venous malformations, and at describing the different therapeutic features of this condition.