Type D personality has recently attracted attention as a psychological factor closely related to the onset and progression of coronary heart disease (CHD). The purpose of the present research was to develop the Japanese version of Type D scale and to evaluate its validity and reliability. Participants (N=291; 133 CHD patients, 158 normal adults) completed questionnaires including the Japanese version of the Type D Scale (DS14), Hospital Anxiety and Depression Scale (HADS), Kikuchi's Social Skills Scale-18 (Kiss-18), and Negative Emotional Suppression Tendency Scale. Exploratory factor analysis of Japanese DS14 revealed two factors (social inhibition: SI, and negative affectivity: NA) comprised of 14 items. Confirmatory factor analysis indicated an adequate index of fitness. In addition, the scale had an acceptable internal consistency (Cronbach's alpha, SI=.862, and NA=.799), as well as adequate reliability. These results indicate that the Japanese version of DS14 is a clinically useful scale for evaluating Type D personality in patients with CHD.