BACKGROUND: Acute bacterial prostatitis is an uncommon male urinary tract infection that is the result of severe prostatic infection mainly by gram-negative bacteria. We conducted a retrospective study to report clinical outcomes of patients with acute bacterial prostatitis. MATERIALS AND METHODS: The clinical records of 49 patients diagnosed with acute bacterial prostatitis were reviewed retrospectively and patients' symptoms, investigations, and treatments were analyzed. RESULTS: All patients presented with fever and voiding symptoms. Some patients (22.4%) had a history of prior manipulation of the lower urinary tract including transrectal prostate biopsy. Urine cultures were positive for 51% of the patients. The most common pathogen was Escherichia coli (60%), followed by Pseudomonas aeruginosa (20%) and Staphylococcus aureus (12%). The ciprofloxacin susceptibility against E. coli was 80%. All patients were treated with parenteral antibiotics in the hospital followed by oral antibiotics for average of three weeks. The major drugs used for empirical treatment were cephalosporins, aminoglycosides, and fluoroquinolones. Prostatic abscess was found in two (4.1%) patients and chronic pelvic pain syndrome developed in six (12.2%) patients during follow-up. CONCLUSION: The currently used empirical antibiotics were mostly effective in the treatment of acute bacterial prostatitis. Continuous monitoring on antimicrobial susceptibility of acute bacterial prostatitis was necessary for providing proper treatment guideline.