BACKGROUND: Since the first national guideline for managing obesity in adults and children in Canada was published in 2007, new evidence has emerged and guideline standards have evolved. Our purpose is to describe the protocol used to update the Canadian clinical practice guideline for managing pediatric obesity. METHODS: This guideline will update the pediatric components of the 2007 Canadian clinical practice guideline for the management of obesity. In partnership with Obesity Canada, we began preliminary work in 2019; activities are scheduled for completion in 2022. The guideline will follow standards developed by the National Academy of Medicine and the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) working group. Guideline development will be informed by 5 complementary literature reviews: a scoping review that focuses on clinical assessment in pediatric obesity management and 4 systematic reviews to synthesize evidence regarding families' values and preferences as well as the safety and effectiveness of interventions (psychological and behavioural; pharmacotherapeutic; and surgical). We will use standard systematic review methodology, including summarizing and assessing the certainty of evidence and determining the strength of recommendations. Competing interests will be managed proactively according to recommendations from the Guidelines International Network. Diverse stakeholders, including families and clinicians, will be engaged throughout guideline development. INTERPRETATION: The guideline will support Canadian families and clinicians to make informed, value-sensitive and evidence-based clinical decisions related to managing pediatric obesity. The guideline and accompanying resources for end-users will be published in English and French, and we will partner with Obesity Canada to optimize dissemination using integrated and end-of-project knowledge translation.