Objective To explore the cognitive function of bipolar disorder Ⅱpatients with aggressive behavior. Methods Sixty bipolar disorder Ⅱpatients in Department of Clinical Psychology，People’s Hospital of Xinjiang Uygur Autonomous Region were enrolled. Selfcompiled inventory， Hypomania Check List (HCL-32)，Barratt Impulsivity Scale-11 (BIS-11)，Modified Overt Aggression Scale (MOAS) and Wisconsin Card SortingTest (WCST) were tested. Patients were divided into aggressive group (n=30) and non-aggressive group (n=30)according to scores of MOAS. Results There was no significant difference in HCL-32 score between aggressivegroup and non-aggressive group. The scores of motor impulsiveness aspect in BSI-11 and the first classification in WCST of aggressive group were significantly higher than non-aggressive group (P ＜0.05). Conclusion Bipolardisorder patients with aggressive behavior show more obvious motor impulsive，but similar executive function with patients without aggressive behavior. Aggressive behavior can’t be regarded as an external factor to predict further damage of cognitive function.