The treatment of suprasellar cysts is controversial and most often disappointing: on the one hand, subfrontal approaches to the cysts, in view of removal or fenestration, are frequently dangerous and ineffective; on the other hand, ventricular shunting frequently leads to the paradoxical increase in the size of the cyst. Because of these difficulties, the authors have treated 17 consecutive cases by the means of a percutaneous transfrontal ventriculocystostomy. In 11 cases, the cyst was perforated by a leukotome which was guided radiologically in 10 cases and by ultrasounds in 1 case. In the remaining 6 patients, the cystostomy was achieved by a monopolar coagulation under ventriculoscopic control. The results were as follows: in 3 cases, it was not possible to achieve the fenestration of the cyst with the leukotome due to the resistance of the membrane; in 1 case, the ventriculocystostomy was complicated by a poor control of the trocar progression under ultrasounds; the other 14 procedures were successful: signs of increased I.C.P. disappeared; the neurological symptoms regressed; the cysts diminished in size. However, the preoperative endocrine troubles did not decrease. The persistence of a post operative ventriculomegaly apparently did not affect the level of the intellectual development of the patients. The authors emphasize the interest of the percutaneous ventriculocystostomy, this procedure being simple, benign and efficacious. The fenestration of the cyst by coagulation appeared more suitable than by the leukotome.