This work analyzes how the assumption of responsibility by aggressors convicted for gender-based violence is related to sexist attitudes, self-esteem and perceived functional social support. Similarly, the predictive capacity of these variables is studied with respect to the aggressors' minimization of the harm done and a lack of attributing responsibility to themselves. The participants in the research were males condemned to prison sentences for crimes related with gender-based violence in Spain. The instruments applied were the Attribution of Responsibility and Minimization of Harm Scale, the Ambivalent Sexism Inventory (ASI), the Rosenberg Self-Esteem Scale (RSE), the Functional Social Support Questionnaire (FSSQ), and the Social Desirability Scale (SDS). The study concludes that sexist attitudes are related with a greater lack of attribution of responsibility, as well as with a greater tendency to minimize the harm done by the aggression. In addition, the aggressors with low self-esteem use self-defense as a strategy to justify the violence. Similarly, the presence of an adequate social support network for the aggressor increases the attribution of responsibility on the part of those convicted for gender-based violence.