Objective To evaluate the value of magnetic resonance imaging (MRI) in screening for prostate cancer. Methods A total of 120 patients with a confirmed diagnosis of prostate cancer were enrolled in Nanjing Municipal First Hospital from March 2020 to March 2023, and 100 age-matched health volunteers during the study period served as controls. All patients and healthy individuals received prostate MRI scanning, and apparent diffusion coefficient (ADC) was estimated. Post-surgical pathology was used as a gold standard to evaluate the sensitivity and specificity of MRI in screening for prostate cancer. The correlation between pathological staging and ADC values in prostate cancer patients was investigated using Spearman correlation analysis. Results The mean ADC values were (1.01 ± 0.15) × 10⁻³, (0.88 ± 0.21) × 10⁻³, (0.72 ± 0.11) × 10⁻³, and (0.59 ± 0.09) × 10⁻³ mm²/s, respectively, for stage A, B, C, and D prostate cancer patients, and the differences were significant (F = 38.99, P < 0.01).Pearson correlation analysis showed a significant negative correlation between pathological staging and ADC value (r = −0.81, P < 0.05). In addition, the sensitivity and specificity of MRI in prostate cancer screening were 92.50% and 91.00%, respectively. Conclusion MRI shows a high value in screening for prostate cancer, and the ADC value is of great significance for staging prostate cancer.