Background and Objective: Being regarded as the second most common malignancy worldwide in men, prostate cancer (PCa) represents about 15% of all diagnosed male cancers. The diagnosis and staging are clinically significant for diseases, and the early identification of PCa could contribute to relatively favorable prognosis. It is vital to identify lesions in time and more accurately before pharmaceutical drugs or surgeries. Magnetic resonance imaging (MRI) and Computed Tomography (CT) are both the reference standard imaging diagnostic methods for patients with local PCa in clinical practice. The purpose of this study was to evaluate the clinical diagnostic value of CT and MRI for patients suffering from PCa. Methods: This retrospective investigation was approved beforehand by the institution ethics committee in our hospital. After comprehensive and systematic retrieval of clinical databases, the eligible patients were enrolled in our hospital, between the dates of January 2011 to January 2017. The data from the patient medical records was retrieved, respectively, and then all the information of pathology and imaging was extracted subsequently. The comparison of diagnostic efficiency between MRI and CT was performed in further. Results: 178 PCa patients were identified finally, and the mean age was 67.5 years old (range: 51-92 years old). And, the majority of PCa came from peripheral zone, and several lesions invaded central gland. The accuracy rates of CT diagnosis were 52.78% in A stage, 45.90% in B stage, 82.67% in C stage, and 66.67% in D stage, respectively. The accuracy rates of MRI diagnosis were 80.56% in A stage, 85.25% in B stage, 86.67% in C stage, and 83.33% in D stage, respectively. The accuracy rates of CT combined with MRI diagnosis were 88.89% in A stage, 96.72% in B stage, 74.67% in C stage, and 83.33% in D stage, respectively. And, the total diagnostic efficiency of CT was 63.48%, MRI 84.83%, and the combination of CT and MRI 93.82%. Conclusions: MRI performed better than CT, and the combination of MRI and CT performed better than MRI, in terms of detecting PCa. In spite of several promising results we obtained, the further analysis and validation are still required in this field, on account of the single-center retrospective design.