This research examined the effect of implicit theories of personality on interpersonal forgiveness and the mediating mechanism underlying this effect. Two experiments show that incremental personality theorists are less forgiving than entity personality theorists and that this difference can be explained by the incremental theorists' stronger tendency to appraise the transgressor as responsible for causing the hurtful event. The same findings were obtained regardless of whether forgiveness was measured by self‐report or assessed as responses to anger words in a latency response task.