The aim of this study is to obtain data for improving a training program for patients with diabetes mellitus. One hundred eighty-seven patients with non-insulin dependent diabetes mellitus were tested with 20 questions about their knowledge for self-management of diabetes mellitus. Then to draw out factors in their personal backgrounds relating to their correct answers, multiple regression analyses were conducted. As a result, four factors showed significant differences in the following order: Educational careers > ages > duration of disease > socioeconomic strata. The results of the present study have shown for the first time, that these four factors closely concern patients to acquire the necessary knowledge for their self-management of the disease. In addition, this study has raised some fundamental problems regarding the training program for patients: how education should be given to patients.</p