Cognitive models of social anxiety and depression posit that hostile interpretation bias may be a symptom of, and act as a maintenance factor for, these disorders. Social anxiety and depression are also associated with increased experience of angry and irritable mood. To investigate whether hostile interpretation bias is related to symptoms of the disorder or to irritability, the current study investigated the degree to which state irritable mood may influence these relationships. In two samples, MTurk workers (Sample 1, n = 145) and college students (Sample 2, n = 387), we assessed depression symptoms, social anxiety symptoms, irritable mood, and hostile interpretation bias. In sample 1, depression and social anxiety symptoms were positively associated with hostile interpretation bias. When statistically controlling for irritable mood, depression symptoms no longer significantly predicted hostile interpretation bias. However, social anxiety remained a significant predictor of hostile interpretation bias even when controlling for irritable mood. The pattern of results was identical in sample 2. Results indicate that the association between depression symptoms and hostile interpretation bias may be accounted for by irritable mood, but social anxiety symptoms have a unique association with hostile interpretation bias even when including irritable mood. Clinical implications and future directions are discussed.