Abstract: The invention relates to a method for evaluating, via biodosimetry, the irradiation dose received by a person subjected to ionizing radiation. Said method comprises: a) sampling, in at least one area of the body of the person, the follicles or bulbs of head and/or body hair of the person; b) extracting proteins from cells of said sampled hair bulbs or follicles, wherein said proteins, including proteins from the ATM system, are subjected to phosphorylation and/or acetylation induced by ionizing radiation; and c) analyzing at least two types of extracted proteins and interpreting the analysis results in order to determine the irradiation dose in the or each sampling area.