1) The basal narcosis using Ravona, Amithal and 2% Pantopon scopolamine made no variation of blood coagulating time and platelets number. 2) During the intravenous anesthesia with Penthothal sodium the blood coagulating time was delayed temporally directly after the anesthesia. Concurring with it the number of platelets decreased but soon recovered. At this time the decrease of platelets was striking especially in the venous blood. 3) During the endotracheal anesthesia with cyclopropaine the blood coagulating time was reduced one hour after the anesthesia temporally. It was then delayed with the progress of anesthesia. The blood platelets increased and decreased according with it. They were striking in the venous blood. 4) During the endotracheal anesthesia with ether the blood coagulating time showed a distinct reduce with the progress of anesthesia and even after the end of the anesthesia its recovery was delayed. The blood platelets distinctly increased and its recovery was also distinctly delayed. These variations were characteristically more striking in the arterial blood. 5) By the anesthesia using cyclopropaine and nitrous oxide together the variation of blood coagulating time and platelets number were alike to that during the anesthesia with cyclopropaine, but they were very variable after the anesthesia. 6) The platelets variation in all kind of anesthesia was parallel with that of blood coagulating.