The importance of psychopathy for perpetration and maintenance of intimate partner violence (IPV) has been speculated. However, less is known about whether psychopathy would explain a psychophysiological response (cardiorespiratory and electrodermal) of IPV perpetrators dealing with acute stressors. Therefore, we first aimed to assess whether IPV perpetrators (n = 58) showed differences in psychopathic traits and their psychophysiological response to acute stress compared to nonviolent men (n = 53). Second, we examined in both groups whether psychopathic traits would explain a psychophysiological response when dealing with acute laboratory stress. Our results revealed that IPV perpetrators differed from controls in all the psychopathic traits, scoring higher on all psychopathy scales. Moreover, IPV perpetrators showed lower total respiratory sinus arrhythmia (RSA) levels than controls. Finally, regarding high total psychopathy scores, factor 1 and affective facet entailed low RSA levels in both groups and scoring high in lifestyle facet of factor 2 explained reduced heart rate (HR) changes in response to acute stress in both groups. All these results highlighted that a reduced vagal tone could be characteristic of psychopathic traits, especially for the affective facet of psychopathy. Therefore, it would be important to incorporate biological markers in combination with psychological measurements to clearly diagnose IPV perpetrators before starting intervention programs. This would increase our ability to improve IPV intervention therapeutic targets and reduce risk of recidivism.