It has been shown that vitamin D by activating the VDR can regulate the expression of genes involved in the regulation of growth, cell differentiation and apoptosis. In addition, many studies suggest that vitamin D may have anti-inflammatory and immunomodulatory effects that may play a role in the prevention of prostate cancer (PCa), although some previous studies have suggested an inverse relationship between vitamin D and the risk of PCa. This case-control study aimed to investigate the association between deficient and insufficient levels of 25-(OH) vitamin D3 and the risk of PCa. A total of 43 cases diagnosed with PCa and 60 controls were included in the study. Blood samples were taken to measure 25-(OH) vitamin D3 and PSA levels. Vitamin D deficient and insufficient levels were defined based on established thresholds. The chi-square test was used for qualitative variables to assess the differences in vitamin D levels between the two groups, the cases and controls, and for quantitative variables, the student t-test was used. The results of the study revealed a strong inverse association (p= 0.008) between deficient levels of 25-(OH) vitamin D3 and an increased risk of PCa. The prevalence of vitamin D deficiency was 16% in the overall population studied and 20.9% in cases diagnosed with PCa. Based on our results, cases with vitamin D deficiency had a significantly higher risk of developing PCa compared to those with sufficient levels. However, further research studies are needed to elucidate the underlying mechanisms and explore the potential of vitamin D supplementation as a preventive strategy for PCa.