Abstract: Objective To study the pathologic features and differences of tissue inflammation in benign prostatic hyperplasia (BPH) and prostate cancer (PCa). Methods The HE stained slice obtained by prostate biopsy from 143 BPH and 106 PCa were reviewed to determine whether the tissue inflammation existed. According to the histological classification of prostatic tissue inflammation, the features of tissue inflammation and the differences of these features between the two groups were studied in detail. Results There were 142 cases found tissue inflammation in 143 BPH patients and 104 cases in 106 PCa patients, so the incidences of tissue inflammation in BPH and PCa were 99.3% and 98.1% respectively. The anatomical location of inflammation was significant difference between BPH and PCa group (P<0.05). The peri-glandular inflammation (56.3%) was primary in BPH, and interstitial inflammation (56.7%) was the main pattern in PCa. The inflammation range was also significant difference between the two groups (P<0.05). The inflammation was presented multifocally (60.6%) in BPH, and focal lesions (51.0%) was commonly found in PCa. Mild inflammation was most frequently observed in both groups (P>0.05). However, there were statistically significant differences between the two groups in the degree of moderate and severe inflammation (P<0.05). Conclusion The incidences of tissue inflammation were high in both BPH and PCa, but the pathological features of tissue inflammation were different between BPH and PCa.