Importance: No case series or cohort studies to date in the English literature have evaluated sudden sensorineural hearing loss (SSHL) in patients with human immunodeficiency virus (HIV).Objective: To investigate the risk of developing SSHL in patients with HIV.Design and Setting: Retrospective cohort population-based study using data from the Taiwan National Health Insurance Research Database.Participants: In total, 8760 patients with HIV and 43 800 control subjects without HIV were selected from insurance claims between January 1, 2001, and December 31, 2006.Main Outcome Measure: The incidence of SSHL was assessed and determined at the end of 2009.Results: Among patients aged 18 to 35 years, the incidence of SSHL was 2.17-fold higher in the HIV group than in the control group (4.32 vs 1.99 per 10 000 person-years, P=.03). The risk of developing SSHL increased with HIV infection; an adjusted hazard ratio of 2.169 (95% CI, 1.071-4.391) was calculated using a Cox proportional hazards regression model. Among male patients, the incidence of developing SSHL was 2.23-fold higher(95% CI, 1.06-4.69) in the HIV group than in the control group. The incidence of SSHL did not differ significantly between the HIV group and the control group for patients 36 years or older.Conclusion and Relevance: Human immunodeficiency virus infection is significantly associated with an increased risk of developing SSHL in patients aged 18 to 35 years, particularly among male patients. JAMA Otolaryngol Head Neck Surg. 2013; 139(3): 251-255. Published online February 21, 2013. doi: 10.1001/jamaoto.2013.1709