Japan has one of the highest suicide rates in the world. Suicides numbered 32,863 in 1998 and have exceeded 30,000 in every subsequent year. Education of those involved in general and psychosocial patient care can contribute greatly to suicide prevention. The authors administered a brief knowledge and attitude assessment questionnaire concerning suicide to students in their first, third, and fifth years at a Japanese medical school. Participants numbered 160 (94 men with a mean age of 21.8 years, SD = 3.01, and 66 women with a mean age of 21.2 years, SD = 2.64); 59 first year, 52 third year, and 49 in their fifth year. The questionnaire consists of eight multiple-choice questions asking knowledge of suicide and one open-ended question asking attitude. In the knowledge part, only about half of the items were answered correctly (mean score was 4.21, SD = 1.28). A significant difference was observed in prevalence of attitudes as categorical variables between student years (P = 0.001). Sympathetic comments increased along with student years, while critical comments decreased. Given the frequent and interventional opportunities of primary-care medical contacts, poor understanding of suicide from the medical viewpoint was of concern. Moreover, judgmental attitudes were common, especially in earlier school years. Better informed, more understanding physicians and other health professionals could contribute greatly to prevention.