Alcohol effect expectancies have important implications in our understanding drinking behavior and motivations for drinking. Several instruments have been developed to asses alcohol expectancies among various populations. Although co-occurrence of PTSD among those with alcohol use disorders is extremely common, there is no measure of PTSD-related alcohol expectancies. The Post-traumatic stress disorder-Alcohol Expectancy Questionnaire (P-AEQ) is a 27-item, self-report questionnaire that was developed to measure individuals' beliefs about the effects of alcohol with regard to symptoms of post-traumatic stress disorder. The P-AEQ was found to measure two primary dimensions, positive and negative alcohol effect expectancies. This instrument demonstrated internal consistency, reliability, and concurrent validity within the Alcohol Expectancies Questionnaire. In addition, the P-AEQ appears to be capable of differentiating AUD from non-AUD populations in a male veteran sample.