A study was carried out on the clinical response to antibiotics in 105 patients with chronic bacterial prostatitis. Two groups of patients were compared in a retrospective study. The results of rectal examination, ultrasound scan, microbiological analysis, and response to different antibiotic therapy regimens were compared. There was a high incidence of perineal-testicular pain and sexual potency reduction; prostate congestion and pain on rectal examination were frequently reported. All the patients had positive microbial cultures, with Gram-negative microorganisms being predominantly isolated. Following the administration of different antibiotic therapy regimens, symptoms either disappeared or diminished, irrespective of whether positive cultures remained. A poorer clinical response was observed in patients with positive prostate ultrasound and rectal examination, and with isolated Gram-negative bacilli. No differences were observed between either group in clinical response to different antimicrobial regimens.