The Antisocial Personality Questionnaire developed by Blackburn and Fawcett (1999) has shown adequate reliability and validity in studies of male offenders interned in psychiatric hospitals. This paper provides data on the APQ collected from a sample of offenders (males and females) without any diagnosed mental illness. The sample was made up of 216 offenders (108 males and 108 females) confined in Spanish prisons. We analyzed the psychometric properties of the instrument and we also examined differences in personality as a function of gender and type of crime (violent vs. non-violent). Results support the reliability of the APQ scales as well as the structure proposed by Blackburn. Additionally, we selected items that discriminate between offenders convicted for violent and non-violent crimes; when these items are factorized, a three-factor structure emerges, resembling Eysenck's model.