Background <p>Dietary adherence is a critical component of managing chronic kidney disease (CKD) and its associated complications. However, patients with CKD often struggle to adhere to dietary recommendations due to various barriers and facilitators that influence their behavior. Existing reviews on this topic have been limited in scope or have not used a theoretical framework to guide the analysis. This systematic review aims to identify and synthesize the evidence on barriers and facilitators to dietary adherence in CKD patients using the Theoretical Domains Framework (TDF) to categorize the identified factors. Using a PICo framework: Population—adults with chronic kidney disease (all stages); Phenomena of Interest—barriers and facilitators to dietary adherence; Context—any healthcare setting globally; Outcomes—TDF-categorized factors influencing dietary adherence and their associations with adherence measures.</p> Methods <p>We will conduct a comprehensive search of electronic databases (PubMed, Web of Science, Embase, CINAHL, MEDLINE, The Cochrane Library, PsycINFO, and Scopus), grey literature, and reference lists of included studies to identify quantitative, qualitative, and mixed-methods studies that report on barriers and facilitators to dietary adherence in adult CKD patients. Two independent reviewers will screen studies for inclusion, extract data, and assess the risk of bias using established tools (NOS, CASP, MMAT, RoB 2). We will use a narrative synthesis approach guided by the TDF to categorize and synthesize the findings. If appropriate, meta-analyses will be conducted for specific outcomes or associations. Potential meta-analyses may examine associations between specific barriers/facilitators and dietary adherence measures, biochemical outcomes (e.g., serum phosphorus, potassium levels), or clinical outcomes where sufficient homogeneous data are available. The GRADE and GRADE-CERQual approaches will be used to assess the overall quality of evidence.</p> Discussion <p>This systematic review will provide a comprehensive and theoretically informed synthesis of the barriers and facilitators to dietary adherence in CKD patients. The findings will inform the development of targeted interventions, patient education strategies, and future research priorities in the field of CKD dietary management. By using the TDF to guide the analysis, we will provide a structured understanding of the complex factors influencing dietary adherence, which can inform the design of theory-based interventions to improve patient outcomes.</p> Systematic review registration <p>PROSPERO CRD42024571389</p>