The object of the invention is to provide an electron beam lithography apparatus and a method thereof which, while maintaining a predetermined pattern drawing accuracy, enables the pattern drawing speed to be improved still further. An electron beam lithography apparatus comprising exposing an electron beam 2 from an electron gun 1, interrupting the electron beam 2 by means of a blanker 6, further deflecting the electron beam 2 by applying a voltage to a deflector 7, wherein the electron beam lithography apparatus is characterized by selecting one of a first predetermined period of time required for the voltage of the deflector 7 to be stabilized and a second period of time which is shorter than the foregoing first period of time, and wherein the blanker 6 is operated according to the result of the foregoing selection.