Objectives: We report the first case of writing apraxia as the main presenting feature of a posterior communicating artery aneurysm. Cerebral aneurysm usually presents with visual impairment, nausea and vomiting, severe headache and loss of consciousness. Case report: A 58-year-old man presented to the neurological department because of writing difficulty, which affected his work as an executive. Detailed clinical examination and supplementary radiological investigations confirmed a posterior communicating artery aneurysm. The patient was treated surgically with clipping of the aneurysm and he had full recovery at clinic review. Conclusion: To the best of our knowledge, there has been no previous report of a posterior communicating artery aneurysm presenting with writing apraxia. Our case is unusual because the patient’s main presenting feature was writing apraxia secondary to a posterior communicating artery aneurysm.