Chronic prostatitis typically occurs in aging men, and its symptoms include frequent and painful urination. In recent study, several studies have shown that Korean red ginseng (KRG) can be used in the prevention and treatment of various diseases. The objective of this study is to investigate whether KRG can play a role in repressing the development of chronic nonbacterial prostatitis (CNP) in male Wistar rats. To induce CNP, rats were castrated and beta-estradiol (0.25 mg/kg) was subcutaneously (s.c.) injected daily. 7-week-old male Wistar rats were divided into 5 groups (the normal group, CNP group, positive group, and KRG group (0.25g/kg) and another KRG (0.50g/kg) group. After 4 weeks, all rats were sacrificed and their prostate and serum were analyzed. Compared to the positive group, the KRG groups (0.25g/kg and 0.50g/kg) showed similar protective properties on CNP based on the histopathologic morphology of the prostate and the inflammation cytokines in the prostate tissue. Also, results of the immunohistochemistry staining showed that expression levels of vascular endothelial growth factor A (VEGFA), interleukin 6 (IL6), interleukin 1 beta (IL-1ß), tumor necrosis factor (TNF-alpha), and cytochrome c oxidase subunit II (COX2) were also decreased in KRG group (0.25g/kg) and KRG group (0.50g/kg). These results suggested that KRG inhibited the development of CNP and might a useful herbal treatment or functional food for CNP.