An electron beam irradiation method includes calculating a charge amount distribution in the case where a substrate is irradiated with an electron beam, by using an index indicating complexity of a pattern to be formed on the substrate, calculating a positional deviation amount of an irradiation pattern to be formed due to irradiation with the electron beam, by using the charge amount distribution having been calculated, correcting an irradiation position by using the positional deviation amount having been calculated, and applying an electron beam to the irradiation position having been corrected.