Williams syndrome (WS) is associated with an unusual profile of anxiety, characterised by increased rates of non-social anxiety but not social anxiety (Dodd and Porter, J Ment Health Res Intellect Disabil 2(2):89-109, 2009). The present research examines whether this profile of anxiety is associated with an interpretation bias for ambiguous physical, but not social, situations. Sixteen participants with WS, aged 13-34 years, and two groups of typically developing controls matched to the WS group on chronological age (CA) and mental age (MA), participated. Consistent with the profile of anxiety reported in WS, the WS group were significantly more likely to interpret an ambiguous physical situation as threatening than both control groups. However, no between-group differences were found on the ambiguous social situations.