Violence is a serious public health problem and has a high impact on the quality of life of individuals across societies. Evolutionary, genetic, environmental, and cultural factors are closely interconnected as morbid causes. Animal models can be an important tool in the study of aggression. Regrouped Swiss Webster mice were selected based on mobility profile (Hypo, Normal; Hyper), which was defined by the tail suspension test. Our results demonstrate that Hyper mice (anxiety-like behavior) were more aggressive and violent than the other two categories, indicated by a pattern of aggressive behavior with a score 4+ in relation to score 1+ of Normal category. Hyper group, showed a decrease in total testosterone levels (-32.5% in relation to Norm group) and an increase in progesterone levels (+57.6% compared with the Norm group). We also observed a decrease in the weight of the testicles, the seminiferous tubules, Leydig and diploid spermatogenic cells number in hyper aggressive animals. Together, the results indicate an association between testosterone/progesterone and the appearance of highly aggressive behavior in male Swiss Webster mice. CEUA/FIOCRUZ, #LW-5/12.