Objective The study intended to assess the pooled prevalence of vitamin D deficiency (VDD) and its associated factors among patients with type 2 diabetes mellitus (T2DM). Design The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were employed to plan and conduct this systematic review and meta-analysis. Data sources PubMed, Medline, Google Scholar, Web of Science, Science Direct and the Worldwide Science database were searched from their inception to 31 January 2023. Methods Data were extracted using a standardised data extraction format prepared in Microsoft Excel. The inverse variance (I2) test was used to evaluate the presence of heterogeneity across the included studies. To identify the possible source of heterogeneity, subgroup analysis was carried out. Funnel plot symmetry, Begg’s and Egger’s tests were used to evaluate the existence of publication bias. In addition, factors associated with VDD among patients with T2DM were examined. All statistical