An electron beam irradiation device which can uniformly project electron beams to the entire outer surface of a container by using a small-sized low-energy electron accelerator, can maintain reliability and safety of a sterilization effect high by making sterilization levels of portions to the same and can keep a cost of the electron accelerator and an initial cost and a maintenance cost of the device low by prolonging a usage limit (service life) is provided. When each of the side surface portions of the container is irradiated with the electron beams by supporting a bottom surface portion of the container by a supporting portion, a position of the container is moved by the supporting portion so that a distance between each of the side surface portions of the container and an irradiation window of the electron accelerator is made substantially equal. Subsequently, when an upper surface portion and a bottom surface portion of the container are irradiated with the electron beams by holding the side surface portion of the container by a holding portion, the position of the container is moved by the holding portion so that the distances between the upper surface portion and the bottom surface portion of the container and the irradiation windows of the electron accelerators become substantially equal.
