Abstract Introduction: Black males face a higher incidence of prostate cancer compared to other racial and ethnic groups. Cardiovascular disorders, including hypertension and metabolic syndrome, are more frequently observed in black men with prostate cancer, significantly impacting their quality of life, treatment outcomes, and related challenges. Socioeconomic disparities and stress also pose significant challenges for black men who engage in substance use, such as tobacco or alcohol. The purpose of this study was to explore the prevalence of cardiovascular issues and substance abuse specifically among black males diagnosed with prostate cancer. Methods: This descriptive, cross-sectional study examined associations between substance abuse, cardiovascular co-morbidities, and diagnoses of prostate cancer in men in Nigeria, Africa. It utilized data collected from the Prostate Cancer Transatlantic Consortium (CaPTC) Familial Cohort Study, an ongoing longitudinal cohort study initiated in 2018 which explores risk factors of prostate cancer among African Black men in Nigeria, Cameroon, and the United States (U.S.). Descriptive statistics generated association tables for variables captured. Results: From 708 participants who resided in Nigeria, 117 reported prostate cancer diagnoses compared to 580 who denied any cancer diagnoses. Median age of participants was 50, most were married (98.1%), Christian (65.8%), college educated (29.4%), with professional occupations (29.4%) and an average household income of 1,000,000 + Naira (24.2%). Marijuana use and alcohol consumption were identified to have statistically significant associations with prostate cancer diagnoses (p=0.003, p<0.001, respectively), while smoking (p=0.13), weight (p=0.22), and annual physicals (p=0.39) were not found to be significant predictors of prostate cancer diagnoses. Conclusion: Both marijuana and alcohol use were found to have significant associations with prostate cancer diagnoses in Nigerian men. Further research is directed to explore similar associations in Black men of other locations to confirm. This study provides a glimpse of associations of substance use and cardiovascular concerns in black males with prostate cancer. It is crucial for interventions to identify and understand the role of substance dependence and cardiovascular disorders in black males with prostate cancer to effectively address all risk factors, implementing lifestyle modifications, and providing culturally appropriate care, ultimately improving outcomes and reducing health disparities. Citation Format: Brittany M. Norris, Marvin Fullwood, Daniel Lee, Folakemi Odedina. A descriptive study of substance use and cardiovascular issues among Nigerian men with prostate cancer [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr B123.