Background: Patient research partners (PRPs) are people with a disease who collaborate in a research team as partners. The aim of this systematic literature review (SLR) was to assess barriers and facilitators to PRP involvement in rheumatology research. Methods: The SLR was conducted in PubMed/Medline for articles on PRP involvement in rheumatology research, published between 2017 and 2023; websites were also searched in rheumatology and other specialties. Data were extracted regarding the definition of PRPs, their role and added value, as well as barriers and facilitators to PRP involvement. The quality of the articles was assessed. Quantitative data were analysed descriptively, and principles of thematic content analysis was applied to qualitative data. Results: Of 1016 publications, 53 articles were included; the majority of these studies were qualitative studies (26%), opinion articles (21%), meeting reports (17%) and mixed-methods studies (11%). Roles of PRPs ranged from research partners to patient advocates, advisors and patient reviewers. PRPs were reported/advised to be involved early in the project (32% of articles) and in all research phases (30%), from the conception stage to the implementation of research findings. The main barriers were challenges in communication and support for both PRPs and researchers. Facilitators of PRP involvement included more than one PRP per project, training of PRPs and researchers, a supportive environment for PRPs (including adequate communication, acknowledgement and compensation of PRPs) and the presence of a PRP coordinator. Conclusion: This SLR identified barriers and facilitators to PRP involvement, and was key to updating the European Alliance of Associations for Rheumatology recommendations for PRP-researcher collaboration based on scientific evidence.