Substance abuse, particularly involving tobacco, cannabis, and alcohol, is a growing public health concern among refugee populations due to trauma, displacement, and limited access to healthcare. In Sudan, little is known about the patterns and determinants of substance use among refugees. Objectives: To determine the prevalence of tobacco, cannabis, and alcohol use among refugees in Dubba Province, Dongola State, Sudan, and to identify associated socio-demographic factors, reasons for use, and willingness to seek treatment. Methods: A cross-sectional study was conducted over six months (June–December 2024) in refugee camps in Dubba Province. A systematically selected sample of 444 refugees was drawn from an estimated population of 25,000. Data were collected using a standardized, WHO-adapted self-administered covering sociodemographic information and substance use behaviors. Descriptive statistics and Chi-square tests were used to analyze the data, with significance set at p<0.05. Results: questionnaire Tobacco use was reported by 87.8% of participants, alcohol by 46.8%, and cannabis by 22.3%. Tobacco use showed marginal association with sex (p=0.056), while alcohol use was significantly associated with marital status (p=0.001). Cannabis use showed no significant demographic associations. The most common reasons for use were boredom (39.6%) and experimentation (30.7%). Notably, 88.3% of current users expressed a desire for treatment. Co-use of substances was significant: tobacco and alcohol (p<0.001), tobacco and cannabis (p=0.002), and cannabis and alcohol (p<0.001). Conclusion: Substance use is highly prevalent among refugees in Dubba Province, driven by psychological and environmental stressors. Integrated prevention and treatment strategies are urgently needed in refugee settings.