Purpose: We held workshops (WSs) that recommend the use of advance care planning (ACP) for medical and health care professionals, and clarified whether or not these WSs motivated them to engage in their own ACP using two indicators: the proportion of professionals who wanted to conduct ACP and changes in the Death Attitude Inventory (DAI). Method: After the WS, we divided participants into two groups, depending on whether or not they wanted to have end-of-life discussions with their family and loved ones. The changes in the DAI brought about by the WSs and their impressions of the WS were compared between the groups. Results: A total of 91 participants were analyzed, of which 42 (46.2%) wanted to have end-of-life discussions with their family and loved ones. In both groups, “afterlife view” and “death anxiety and fear” in the DAI were significantly reduced after the WS when compared to attitudes from before the WS. In the group which wanted to have end-of-life discussions, “death avoidance” (effect size −0.42) and “sense of purpose in life” (effect size 0.51) changed significantly and positively. Conclusion: About half of the participants wanted to perform ACP after having attended the WSs, apparently due to an increased sense of purpose in life and a reduced death avoidance.