The aim of this study was to investigate the relationship between developmental factors and deviant sexual preferences in child molesters. In total, 146 adult males having committed a sexual offence against a child were included in the study. Three types of factors were investigated: negative experiences during childhood, behavior problems during adolescence, and sexual criminal activity in adulthood. Negative experiences and behavior problems were assessed through a semistructured interview. The sexual criminal activity was determined using police records. Sexual preferences towards children were assessed using phallometric assessment. Hierarchical regression analyses suggested the presence of two developmental pathways. The psychosocial deficits pathway is related to a sexual interest for nonviolent sexual stimuli involving children. The sexualization pathway is associated with a sexual interest for violent sexual stimuli involving children. These two pathways are discussed in light of previous empirical findings related to the development of deviant sexual preferences in child molesters.