Background: Recent studies have shown that a Type D personality is associated with an increased risk of cardiac mortality. Objective: This study aimed to examine the impact of a Type D personality on clinical and psychometric roperties in a sample of Turkish patients with a first myocardial infarction (MI). Method: The study included 131 patients who were admitted to the coronary care unit of a hospital. All of the patients underwent a psychiatric assessment within 2 to 6 onths after their MI. Psychiatric interviews were conducted using the Structured Clinical Interview for DSM-IV (SCID-I). Patients also completedthe Beck Depression Inventory, the Spielberger State-Trait Anxiety Inventory, the Health Anxiety Inventory, and the Type D personality scale. Results: The patients were divided into 2 groups on the basis of the presence or absence of Type D personality. There was a 38.2% prevalence of Type D personality in the patients with a first MI. Those with this type of personality had a significantly higher frequency of hypertension and stressful life events. The Type D patients also had more psychiatric disorders, including depressive and anxiety disorders, than the non-Type D patients. Conclusions: Our findings suggest that Type D personality traits may increase the risk of hypertension and the risk of psychiatric morbidity in patients with a first MI. We suggest that this type of personality is a contributorto depression and anxiety disorders. These findings emphasize the importance of screening for Type D personality as both a cardiovascular and psychiatric risk marker in patients who have had an MI.