Objective: To examine the relationship between the personal beliefs that patients with auditory hallucinations have concerning their voices and the incidence of aggression toward self, others, and objects on the inpatient ward. Method: Forty actively hallucinating adults were recruited from the psychiatric inpatient service at Bellevue Hospital Center in New York. The beliefs that subjects had about their voices were measured using the revised Beliefs About Voices Questionnaire, and symptom severity was measured using the Positive and Negative Syndrome Scale. Frequency and severity of aggressive acts were measured retroactively over a 2-week peri od using the retroactive Overt Aggression Scale-Modified. The study was conducted from August 2007 to December 2007. Results: Analyses revealed that hallucinators' beliefs that their voices are omnipotent, malevolent, and unable to be resisted accounted for 34% of the variance in predicting aggression on the psychiatric inpatient service. Subsequent stepwise regression analysis determined that hallucinators' belief in the omnipotence of their voices accounted for 21% of variance in predicting aggressive episodes on the inpatient service. Additionally, hallucinators with the strongest conviction in the omnipotence of their voices engaged in almost 10 times more aggressive acts on the inpatient service compared to voice hearers without these convictions. Conclusions: Individuals who believe their hallucinated voices to be all-powerful, malevolent, and irresistible are significantly more likely to engage in aggressive acts on the inpatient service. Examining the beliefs that an individual has about his/her voices may be a useful addition to current aggression risk batteries utilized on acute psychiatric inpatients.