Stalking is characterized by persistent unwanted behaviors and can disrupt the lives of victims. Its prevalence has been increasing with time. Due to the recent criminalization of stalking in Portugal and its being an understudied phenomenon, the objective of this study is to assess the perceptions of police officers (n = 1212) about stalking post intimate relationship breakup. We developed an adaptation of the questionnaire “Reasonable Perceptions of Stalking”, using vignettes that describe stalking scenarios with the manipulation of severity, and victim and perpetrator sex. The main effects of severity, as well as the victim and the perpetrator’s sex, were significant intrasubject variables in the perceptions of stalking and its severity, criminality, victim alert, fear of violence, victim-blaming, and the need for intervention. Participants’ sex, previous training, and personal and/or professional experience with stalking were also significant variables concerning participants’ perceptions. Our findings show that gender stereotypes are still perpetuated and have important implications for police officer training and intervention.