Background: Common carotid artery pseudoaneurysm is an uncommon complication of deep neck space infection. Objective: We reported a case of parapharyngeal space abscess complicated with common carotid artery pseudoaneurysm, and discuss its diagnostic methods and treatment strategies. Case report: An old gentleman was admitted for neck swelling and later complained of neurological symptoms. Imaging showed deep neck abscess, common carotid artery pseudoaneurysm and insular arterial infarct. Conservative treatment was decided due to poor premorbid status. Discussion: 1) Pseudoaneurysm of the common carotid artery is a rare complication of deep neck space infection, as opposed to the internal carotid pseudoaneurysm. 2) Computer tomography, Doppler ultrasound, magnetic resonance imaging and angiogram are good investigation choices. 3) Stenting and embolization by Interventional radiologist replace traditional ligation, re-section and grafting surgery nowadays. Conclusion: Vascular complication involving carotid artery due to deep neck space infection confers high morbidity and mortality.