Single-strand breaks (ssb) and double-strand breaks (dsb) are induced upon K-shell resonant absorption (2152.4 eV) of phosphorus atoms in DNA. A kinetic analysis allows the determination of the cross sections of strand breaks production. The quantum yield for ssb induction is equal to unity, showing that they result from the production of multicharged centres on phosphorus atoms. The ratio dsb/ssb is equal to 0.09. This high value is of the order of magnitude of that found for heavy ion irradiations. The dsb production could be due either to electron capture on the second strand by the multicharged centres, or by interaction of the second strand with Auger electrons produced by the electronic rearrangement of the excited core of the phosphorus atoms.L'absorption resonante des rayons K (2152,4 eV) par les electrons K du phosphore induit la formation de coupures simple brin (ssb) et double brin (dsb) de l'ADN. L'analyse des courbes cinetiques permet de determiner les sections efficaces de coupure. Le rendement quantique de production de ssb etant de 1, on peut attribuer leur formation a la production de centres multicharges. Le rapport dsb/ssb egal a 0.09, est eleve, de l'ordre de celui qui est observe par irradiation aux ions lourds. La production des dsb peut etre due soit a une capture d'electrons sur le second brin par les centres multicharges formes sur le premier, soita l'attaque du second brin par les electrons Auger emis lors du rearrangement.