Heart rate (HR) was employed to compare vicarious affective arousal across three groups of children (aged 7.6 - 11, N = 95): Conduct Disordered (CD) elevated on Callous-Unemotional traits ("CD/CU"), CD low on CU traits ("CD-only"), and "typically-developing" controls, matched in age, gender and socioeconomic background. While watching an emotion evocative film, participants' HR was monitored. Immediately after viewing, self-reported vicarious responses were obtained. Participants also completed the "Bryant Empathy Index". "CD/CU" children displayed lower magnitude of HR change than both "CD-only" and controls. Both CD groups reported fewer vicarious responses and scored lower than controls on the empathy index. These results support distinct deficits across CD subsets, suggestive of distinct mechanisms underlying their antisocial conduct.