This paper aims to investigate the pathological characteristics of CD40/CD40L and NF-κB proteins related to inflammation in benign prostatic hyperplasia (BPH) tissue, as well as the outcomes of inflammation. A total of 120 BPH samples were obtained, and clinical data were gathered. The prevalence of BPH-associated inflammation was 91.7%, while inflammation infiltrates were more likely to be mild, multifocal, and stromal. Patients were divided into grades 0, 1, 2, and 3 according to the grade of inflammation. Serum prostate specific antigen (PSA) levels, prostate volumes, and International Prostate Symptom Score (IPSS) were higher in grade 1, 2, and 3 patients (increasing with the grade) than those in grade 0 patients. In addition, the present study demonstrated that CD40 and CD40L were mainly expressed in prostate epithelial cell membranes and some areas of the cytoplasm, whereas NF-κB proteins were mainly expressed in the cytoplasm and nuclei of glandular epithelial cells and prostatic stromal cells but less likely expressed in normal tissues. In the BPH group associated with inflammation, the positive expression rates of these proteins obviously gradually increased along with an increase in the degree of inflammation. BPH-associated with inflammation is a common condition that is associated with higher prostatic volumes, PSA levels, and IPSS compared with BPH alone. Moreover, CD40/CD40L and NF-κB expressions in BPH tissues were associated with the degree of inflammation and may play a role in BPH.IJCEP Copyright © 2017.