Purpose.Psychopathy has been shown to be related to the onset, frequency, and course of antisocial behaviour in criminal offenders. The purpose of the present study was to use cluster analysis to explore the existence of subtypes of criminal offenders in male inmates, based on the two empirically validated dimensions of psychopathy and several other dimensions previously proposed for differentiating offender groups.Methods.Two hundred male inmates participated in the study. Scores on the two dimensions of the Psychopathy Checklist–Revised (Hare, 1991), the Interpersonal Measure of Psychopathy (Kosson, Steuerwald, Forth,&Kirkhart, 1997), DSM‐IV diagnoses for alcohol and drug abuse/dependence, and anxiety were standardized and were included in two different types of cluster analyses. Both Ward's hierarchical method and K‐means non‐hierarchical method revealed the presence of four subtypes of criminal offenders in the sample. The four‐cluster solution was replicated when the sample was split in half and identical cluster analyses were performed on the two subsamples.Results.Two types of cluster analyses identified four subtypes of criminal offenders in two samples of jail inmates. Two of the clusters resembled primary and secondary psychopaths described in the literature, the third group exhibited some antisocial and psychopathic features, and the fourth group was non‐psychopathic.Conclusions.Findings suggest that considering the individual contributions of the two dimensions of psychopathy in lieu of the construct as a whole may prove useful in identifying relatively homogeneous groups of crimina