Background: Future planning has emerged as a global issue for families of individuals with intellectual and developmental disabilities due to the longer lives and limited long-term services and supports in the adult disability system. While it has received greater attention, most future planning studies only included parents of individuals with intellectual and developmental disabilities within the context of European or American countries. The purpose of this study was to examine future planning among siblings of individuals with intellectual and developmental disabilities in South Korea. Method: In this study, 185 Korean siblings of individuals with intellectual and developmental disabilities responded to a survey. Results: Few siblings engaged in future planning activities and reported a range of barriers to conduct future planning. Further, greater future planning involvement was associated with older siblings, greater advocacy level and greater sibling caregiving. Conclusion: For future research, culturally relevant measures and intervention should be addressed.