Presence of a hypofunctioning pigmented adenoma are commonly asymptomatic and is usually only found during an autopsy. In contrast, hyperfunctioning pigmented adenoma is a rare clinical entity and in the majority of cases results in Cushing's syndrome. In this case study, we report a 66-year-old male who presented instead with the clinical and biochemical features of Conn's syndrome. On laparoscopic adrenalectomy, it was found that the tumour had a functioning black adenoma which does not usually present with Conn's syndrome but rather to that of a Cushing's. The intraoperative changes and histopathological findings are discussed.