The influence of vacancies and interstitial atoms on magnetism in Pu has been considered in frames of the Density Functional Theory (DFT). The relaxation of crystal structure arising due to different types of defects was calculated using the molecular dynamic method with modified embedded atom model (MEAM). The LDA+U+SO (Local Density Approximation with explicit inclusion of Coulomb and spin-orbital interactions) method in matrix invariant form was applied to describe correlation effects in Pu with these types of defects. The calculations show that both vacancies and interstitials give rise to local moments in $f$-shell of Pu in good agreement with experimental data for annealed Pu. Magnetism appears due to destroying of delicate balance between spin-orbital and exchange interactions.
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