<p>Malnutrition in Inflammatory Bowel Disease (IBD) is an important medical issue leading to adverse clinical outcomes. The Global Leadership Initiative on Malnutrition (GLIM) criteria provide a common approach for the diagnosis of malnutrition and are proposed to be used in different clinical conditions and environments. The aim of this scoping review was to review the findings of all available studies that have already applied the GLIM criteria in IBD, to explore GLIM prognostic value, to highlight challenges and concerns, and to identify knowledge gaps for further research. A comprehensive literature search strategy using the databases PubMed/MEDLINE and Scopus was conducted. Eligible studies were peer-reviewed articles published until May 2025 in the English language, only conducted in adult people with IBD. Fifteen studies were included in this review. Great heterogeneity was recorded in the way both phenotypic and etiologic GLIM criteria have been evaluated leading to important differences between studies and not allowing comparisons between them, but also to increased risk of bias in many of these studies. The prevalence of malnutrition using GLIM criteria in IBD was medium-to-high (31.7–60.1%) depending on the methodology each study implemented for the assessment of phenotypic and etiologic criteria. Only two of the included studies prospectively assessed the impact of malnutrition on clinical outcomes with conflicting results. Future research should focus both on the implementation of robust methodologies to apply the phenotypic and the etiologic criteria, but also to explore the impact of malnutrition diagnosis on disease-related clinical outcomes.</p>