104 patients with acute bacterial prostatitis were randomized to an antibiotic therapy group (group I) and an antibiotic plus laser therapy group (group II). Laser therapy was applied ever other day through a trans-rectally inserted fiberoptic probe. Resolution of the symptoms occurred in 87% of the patients in group I and 92% in group II (p < 0.001). Transrectal ultrasound resulted in resolution of the peri-prostatic venous plexus congestion in 43.7% of the patients in group I and 89.7% in group II. In conclusion, the combination of laser therapy and antibiotics in bacterial prostatitis provides both a better resolution of the symptoms and a reduction or disappearance of the peri-prostatic venous congestion.