This study examines mock jurors’ perceptions of a young witness according to whether or not he was described as having an intellectual disability. Our study examined perceptions of a child witness younger (five or seven years) than previously studied. Mock jurors (n = 71) viewed a short video excerpt of a boy recalling a personally experienced event, and then rated him across nine domains of eyewitness ability. The boy was described as either having an intellectual disability or typically developing. Participants rated the child more negatively on dimensions relating to cognitive competence, but not trustworthiness, when he was presented as having an intellectual disability. Participants also watched the child answer a series of suggestive questions; when described as having an intellectual disability he was rated as less accurate in responding to these. The findings have implications for the involvement of children with intellectual disabilities within the legal system.