BACKGROUND: Volunteers are expected to play a key role in children's hospice. However, there is a lack of information about how to cultivate effective volunteer training programs. OBJECTIVE: To verify the effect of a training program on volunteers' confidence in providing learning support and sharing experiences with children with life-threatening conditions and their families in a children's hospice. METHODS: In this pre-post study, participants were 48 undergraduate and graduate students from 3 universities in Japan. They received 5 lectures on children's hospice learning support. They evaluated the training program by rating their self-confidence in meeting each of the 15 program goals on a questionnaire. RESULTS: An exploratory factor analysis of the questionnaire yielded 12 goals in 4 factors: understanding of one's own and others' mental state, accommodating the learning needs of children with life-threatening conditions, understanding and accommodating the physical state of children with life-threatening conditions, and understanding the significance of children's hospice. A paired t test revealed that participants' self-confidence had increased significantly in 3 of these 4 factors after the program. However, the score for accommodating the learning needs of children with life-threatening conditions decreased but not significantly. CONCLUSION: Although it needs some improvements, the program was effective for improving volunteers' self-confidence in and understanding of learning support and sharing experiences with children with life-threatening conditions.