MDPV is a synthetic cathinone illegally marketed and consumed for its psychostimulant effects, which are similar to those produced by cocaine, amphetamines, and MDMA. Clinical reports indicate that MDPV produces euphoria, increases alertness, and at high doses causes agitation, psychosis, tachycardia and hypertension, hallucinations, delirium, hyperthermia, rhabdomyolysis, and even death. In rodents, MDPV reproduces the typical physiological effects of psychostimulant drugs, demonstrating greater potency than cocaine. Nevertheless, its role in aggressive behavior has been reported but not yet experimentally confirmed. Therefore, the aim of this study was to evaluate the effects of acute and repeated MDPV (0.01-10 mg/kg i.p.) administration on aggressive behavior in mice and to compare them with those of cocaine (0.01-10 mg/kg i.p.) administration. To this purpose, the resident-intruder test in isolated mice and the spontaneous and stimulated aggressiveness tests for group-housed mice were employed. The present study shows for the first time that MDPV enhances aggressive behavior and locomotion in mice with greater potency and efficacy than cocaine treatment. Moreover, the aggressive and locomotor responses are enhanced after repeated administration, indicating that a sensitization mechanism comes into play. These results, although from preclinical investigation, are suggestive that human MDPV intake could be a problem for public health and the criminal justice system. Thus, investigation by police officers and medical staff is needed to prevent interpersonal violence induced by the consumption of synthetic cathinones.