Objective. The aim of this study was to identify changes in inflammatory molecules in the blood (plasma) of patients with chronic prostatitis/chronic pelvic syndrome (CP/CPPS) compared with controls. Altered levels indicate a systemic component by possible involvement of the prostate and/or the inner pelvic floor musculature. Material and methods. In 32 patients with CP/CPPS and 37 controls, blood plasma levels of testosterone, macrophage migration inhibitory factor (MIF), tumour necrosis factor-alpha (TNF-alpha), TNF-beta, interleukin-2 (IL-2) and IL-1 beta were measured by enzyme-linked immunosorbent assay. Cortisol in saliva samples was measured in the morning and late evening. All participants answered a questionnaire regarding their health profile. Results. Significantly higher levels of MIF (p = 0.012) were detected in patients. The testosterone level was, contrary to other studies, little lower in patients (p = 0.014; age adjusted). When controls with health issues and patients with a parallel disease were excluded, the MIF and TNF-alpha levels were higher in the patients (p = 0.007, p = 0.016, respectively) than in controls, and the testosterone was slightly lower in patients (p = 0.047). Conclusions. The findings show an immune response extending to the circulatory system, in which MIF makes a significant contribution to CP/CPPS. This study also indicates TNF-alpha as a circulatory component when excluding subjects with concomitant diseases. Both MIF and TNF-alpha have previously been highlighted for other diseases related to chronic pain and here also for CP/CPPS. These results provide further insights into the immunological basis of CP/CPPS.