High intensity focused ultrasound (HIFU) is a method of delivering acoustic energy to a focal point and thus destroying it, causing coagulation necrosis. Repeating the fires, the whole needed volume of organ can be treated without damaging the surrounding tissue. A total of 122 patients with biopsy-proven prostatic cancer (and 2 more patients had only high-grade PIN) have been treated in our clinic for 3.5 years using the Ablatherm device. Seventy one of them entered this study. They were followed up for six months to three years at a regular interval. Follow-up PSA measurements and control sextant biopsies were made. The median PSA nadir 1.5-3.0 months after treatment ranged from 0.10 ng/ml (in low-risk localized prostate cancer group) to 2.50 ng/ml (in patients with disseminated process). Negative control biopsies were registered in 74-77.7% patients with local prostatic cancer and in 60-68% patients with disseminated process. Of all the patients, 90% had undergone transurethral resection of the prostate before HIFU treatment. Such combination improved the efficacy of HIFU and significantly reduced treatment-related morbidity. Urinary stress incontinence grade 2 was observed in 1.6% and grade 3--in 0.8% of all the patients. No other severe complications occurred. The erectile function was preserved in 71.2% patients. Our results demonstrate efficacy and safety of HIFU. HIFU does not exclude other treatment options and can be repeated. HIFU seems to be a valid alternative treatment for patients with contraindications for radical surgery.