Background: Parents with learning disabilities are often assessed as lacking the capacity to parent effectively; however, ecological models of parenting indicate that support from informal social networks (ISNs) can help them successfully maintain family life. This systematic review examined evidence regarding (1) parent and child outcomes associated with support from ISNs and (2) perceptions of the roles of ISNs for parents with learning disabilities. Methods: Peer-reviewed quantitative and qualitative literature was identified through a search of six databases, and a narrative synthesis was subsequently conducted. Results: Twenty-six articles were included in the review. Findings of the quantitative synthesis provided preliminary evidence for a positive relationship between support from ISNs and parental mental health, positive parenting practices and child wellbeing. The qualitative synthesis indicated that parents benefited from ISNs through their provision of practical and emotional support and learning skills. Network characteristics that divided supportive from unsupportive members were also identified. Conclusion: Parents with learning disabilities receive the same positive outcomes from ISNs as other parents, although unique contextual and social challenges may affect their experiences. Future research should explore interventions to build ISNs of parents with learning disabilities that acknowledge their existing strengths as parents and community members.