This case illustrates the rare occurrence of a cystic schwannoma of the neck, presenting clinically and ultrasonographically as a type II second branchial cleft cyst. Histology demonstrated that it was in fact a rare cystic schwannoma, most likely arising from the cervical plexus. This is the first documented case of a cystic schwannoma of the neck being mistaken for a type II second branchial cleft cyst based on clinical and ultrasound findings alone. It suggests that more sophisticated radiological investigations, such as magnetic resonance imaging, may enable accurate diagnosis of a cystic schwannoma of the neck pre-operatively.