The purpose of the work is to estimate the efficiency and follow-ups of the contact chemical litholysis (CCL) of gallstones with methyl-tert-butyl ether (MTBE). The CCL has been carried to 5 women with plural (10-15) radiolucent gallstones, who refused from cholecystectomy. The percutaneous transhepatic puncture of the gallbladder has been executed to them under X-ray and ultrasonic control. Laboratory (general blood analysis, urine analysis, biochemical parameters of blood and bile) and tool (ultrasonic control, cholecystography) researches were carried out before the procedure, during dissolution, 2, 6, 9 months after the CCL. High litholytic activity of MTBE has been revealed by dissolution of cholesterol stones of the gallbladder with use of the above-mentioned agent. Local irritation, allergenic actions and essential collateral reactions were not observed. After the CCL, contractility function of the gallbladder has increased (before the procedure - 23,8 +/- 0,4%, after it - 37,5 +/- 0,8%, p < 0,001).