Past research has associated callous-unemotional traits (CU) in young people with serious conduct problems and antisocial behavior. However, whether CU traits influence implicit attitudes toward violence remains largely unexplored. We assess this hypothesis in two independent samples, a sample of youth with no criminal records (Study 1, N = 86), and in a sample of young offenders (Study 2, N = 61). Both groups were not compared due to theoretical (very different demographics) and statistical reasons (the total sample was insufficient to be able to reach the statistical power required in the comparison of both groups). Further, we use an implicit procedure to examine whether CU traits modulate wanting for violent stimuli. Across two samples of youth, we found little evidence of an association between CU traits and implicit violent cognition. In youth with no criminal records, implicit attitudes toward violence were related to the unemotional factor of CU traits, but unrelated to other factors and to a global CU traits score. CU traits were not associated with implicit attitudes toward violence in young offenders. The latter finding was mirrored in the implicit wanting task. Overall, our findings cast some doubts on the adequacy of implicit measures to assess implicit violent cognition in youth with CU traits. We discuss potential methodological limitations of this research (e.g., characteristics of the sample and performance in the implicit procedures) that may impact our results.