The differential diagnosis of a neck mass encompasses a broad range of possibilities including congenital cysts, inflammatory masses and both primary and metastatic neoplasms. A clear understanding of the normal anatomy of the neck and a high index of suspicion with a detailed history elicitation, proper physical examination and adjunctive test reports all lead to an accurate diagnosis. This is a case report of a thirty three year old lady who presented with a mass in the posterior triangle of neck with paraesthesia and mild weakness of the upper limb of the same side. The diagnostic evaluation revealed possibility of Schwannoma of the Brachial plexus and the surgical management posed a great surgical dilemma and led to cervical 5th and 6th trunk paralysis. We performed a second stage Sural nerve grafting.