Abstract Background: Prostate tumors are one of the most common diseases in the contemporary world, with high mortality rates among oncology patients. This is in both developing and developed countries alike. Aim of Study: To correlate apparent diffusion coefficient (ADC) with Gleason score (GS), TNM staging, and PI-RADSv 2.1 of prostate cancer at 3 Tesla. Patients and Methods: Prospective study has been per-formed on 53 male patients (mean age 66 years) with prostate cancer at Mansoura Urology & Nephrology Centre. All patients underwent pre and post-contrast MR and DWI of the prostatic gland by single-shot echo planar imaging at 3 Tesla scanner. PI-RADSv2.1 of the prostate was achieved. The ADC of prostate cancer was calculated and correlated with GS, TNM staging, and PI-RADSv2.1 of prostate cancer. Results: The mean ADC of prostate cancer was 0.612±0.12 x10-3 mm2/s. There was a significant difference in ADC of GS £6 versus ³7 (p=0.001), T1-2 versus T3-4 (p=0.001), N0 versus N1 (p=0.002), M0 versus M1 (p=0.001) and PI-RADSv2 category 3-4 versus category 5 (p=0.001). The cut-off ADC value used to predict higher GS, higher T stage, presence of nodal spread, distant metastasis, and higher PI-RADSv2 were 0.71, 0.61, 0.63, 0.63, and 0.61 x10-3 mm2/s with an area under the curve of 0.96, 0.85, 0.78, 0.74 and 0.84 and accuracy of 90.9%, 81.8%, 73.6, 64.2 and 73.6% respectively. Conclusion: ADC is correlated with GS, TNM staging, and PI-RADSv2 of prostate cancer. Lower ADC is linked to higher GS, higher T stage, presence of nodal and distant metastasis, and higher PI-RADSv2. So, the ADC might be recognized as a hopeful prognostic parameter of prostate cancer.