A case of spontaneous cerebrospinal fluid (CSF) otorrhoea in a 59-year-old lady is reported. The patient was initially diagnosed and treated for chronic otitis externa. Following the referral by her GP, it was found that her symptom of otorrhoea was secondary to cerebrospinal fluid leak with middle ear encephalocoele. The CSF leak was repaired using a transmastoid approach with fascia, bone paté and fibrin glue. In this paper, we describe an unusual case of spontaneous CSF otorrhoea presenting as otitis externa. We review the pathophysiology of spontaneous CSF otorrhoea, and discuss the pitfalls in the diagnosis of CSF otorrhoea.