Developmental disabilities (DDs) are prevalent and associated with health disparities among children. Family health literacy of parents and/or children is one modifiable factor associated with child health; however, little is known about family health literacy for children with DDs. This systematic review was conducted to determine evidence on associations of health literacy with health outcomes among children with DDs. Medline, CINAHL, Embase, ERIC, PsycInfo, and Web of Science were searched through August 2018. Of 2,768 unique records, 53 full text articles were reviewed and four articles were included. Associations of family health literacy with health outcomes among children with DDs were mixed. Future research should include more diverse samples, greater breadth in health outcomes assessed, and increased methodological rigor.