This study investigates whether quantitative MRI of the prostate reveals differences between ethnicities that can affect diagnosis. This study shows that the different ethnicities, specifically AAs and CAs have different quantitative MRI values that affects the utility of MRI in the diagnosis of PCa. Different thresholds are needed for PCa diagnosis for different ethnicities. Despite more high grade lesions in AA, the ADC and T2 for lesions in AA were nominally higher than in CA. DCE-MRI significantly improves differentiation of PCa from benign tissue in AA, due to significantly higher cancer signal enhancement rate in AA compared to CA.