We compared efficacy and safety of mono- vs quasibipolar transurethral resection (TUR) for 198 patients treated with TUR. The patients were randomized into two groups by the TUR variant: mono-or quasibipolar. Comparison ofpre- and postoperative examinations data in the above two groups demonstrated: blood sodium decreased more in patients from monopolar TUR group, the absence of TUR-syndrome and less frequent and severe symptoms of obturator nerve irritation after quasibipolar TUR. Use of salt solution in quasibipolar TUR allowed us to avoid such a severe postoperative complication as TUR-syndrome. Thus, transurethral resection in physiological solution is an operation of choice in surgical treatment of prostatic adenoma and superficial cancer of the urinary bladder.