The management of chronic prostatitis/ chronic pelvic pain syndrome type III (CP/CPPS) has been always considered complex due to several biopsychological factors underling the disease. In this clinical study, we aimed to evaluate the efficacy of the treatment with Curcumin and Calendula extract in patients with CP/CPPS III.From June 2015 to January 2016 we enrolled 60 consecutive patients affected by CP/CPPS III in our institution. Patients between 20 and 50 year of age with symptoms of pelvic pain for 3 months or more before study, a total National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) score ≥ 15 point and diagnosed with NIH category III. Patients were then allocated to receive placebo (Group A) or treatment (Group B). Treatment consisted of rectal suppositories of Curcumin extract 350 mg (95%) and Calendula extract 80 mg (1 suppository/die for 1 month). Patients of Group B received 1 suppository/die for 1 month of placebo. The primary endpoint of the study was the reduction of NIH-CPSI. The secondary outcomes were the change of peak flow, IIEF-5, VAS score and of premature ejaculation diagnostic tool (PEDT).A total of 48 patients concluded the study protocol. The median age of the all cohort was 32.0 years, the median NIH-CPSI was 20.5, the median IIEF-5 was 18.5, the median PEDT was 11.0, the median VAS score was 7.5 and the median peak flow was 14.0. After 3 months of therapy in group A we observed a significant improvement of NIH-CPSI (-5.5; p < 0.01), IIEF-5 (+ 3.5; p < 0.01), PEDT (-6.5; p < 0.01), peak flow (+2.8; p < 0.01) and VAS (-6.5; p < 0.01) with significant differences over placebo group (all p-value significant).In this phase II clinical trial we showed the clinical efficacy of the treatment with Curcumin and Calendula in patients with CP/CPPS III. The benefits of this treatment could be related to the reduction of inflammatory cytokines and of inflammatory cells. These results should be confirmed in further studies with greater sample size.