Few studies have been performed to examine the effects of educational intervention for oncologists in Japan, to update their knowledge and skills regarding palliative care. This study is aimed to evaluate not only the improvement in trainees’ knowledge and self-complacency, but also to focus on the factors associated with the actual clinical practices of trainees. In one year, 323 trainees from the Hiroshima prefecture joined palliative care workshop using the Palliative Emphasis program on symptom management and Assessment for Continuous medical Education (PEACE), and they were included as subjects in the present study. Referring to the contents of the program, a questionnaire was developed to estimate the extent of change in the trainees’ attitude towards clinical practice. Each of the 26 items included a five point Likert scale ranging from “mostly take responsibility for symptom management” to “depends mostly on the experts for direct intervention”. The questionnaire survey was conducted before and after the implementation of the PEACE program. From the 206 valid responses, most of the data items showed a significant and positive shift in the trainees’ attitude toward palliative care in a clinical setting. Items that did not show this change pertained to adjustment of antidepressants and tranquilizers for delirium and depression. These results suggest that the PEACE program may be effective in improving physicians’ attitudes regarding palliative care.