Abstract: In order to investigate the pharmacological effect of Paeonia suffruticosa Andr. stamens on chronic non-bacterial prostatitis (CNBP) in rats, the rats with chronic abacterial prostatitis induced by castration combined subcutaneous injection of hormone (estradiol benzoate 0.25 mg·kg⁻¹) were used as models. Forty rats with CNBP were randomly divided into five groups (8 per group): Model group (normal saline), positive group (celecoxib 250 mg·kg⁻¹), various doses of lyophilized powder of Paeonia suffruticosa Andr. stamens groups (100, 200, 400 mg·kg⁻¹). Another group of normal mice treated with normal saline as normal group. The therapeutic effect of Paeonia suffruticosa Andr. stamens on CNBP was evaluated by lecithin body density, prostatic index, cytokines in prostate tissue and the expression levels of TXB2 and 6-K-PGF1α in blood. The results showed that the inflammation of prostate tissue in rats was significantly improved. Compared with model group, the number of white blood cells, prostate weight, prostate index, TXB2 and the content of PGE2 in prostate tissue of rats were significantly decreased in each dosage group of Paeonia suffruticosa Andr. stamens (P<0.01, P<0.05). The contents of ICAM-1, INF-γ, TNF-α, MCP-1 and IL-8 in high-dose group of Paeonia suffruticosa Andr. stamens were significantly decreased (P<0.01, P<0.05), and in low-dose group were also decreased, but there was no significant difference (P>0.05). The contents of 6-keto-PGF1α and NO in high dose of Paeonia suffruticosa Andr. stamens were significantly increased (P<0.01, P<0.05), and in low dose group were also increased, but there was no significant difference (P>0.05). This study showed that Paeonia suffruticosa Andr. stamens had therapeutic effect on chronic abacterial prostatitis, which would provide a theoretical basis for further development and application of the Paeonia suffruticosa Andr. stamens.