Mr X, 29 years old, has suffered from mood disorder with behavioral and temperamental disorder since his childhood. This association of bipolar disorder and pathological personality makes the patient's evolution complex with integration and relationship difficulties leading him to episodes of depression and hypomania after antidepressant treatment. This comorbidity raises different questions: are personality features a consequence of bipolar disorder? Are they a predisposition to bipolar disorder? Do they influence the outcome? Are they a minor form of bipolarity? Our hypothesis in this case was that the patient had a bipolar disorder since his childhood. The personality features are considered as a form of bipolarity.