New physics searches in ATLAS and relation to astroparticle physics

The existence of Dark Matter (DM) is by now well established, and the fit of the cosmological model parameters to various measurements lead to a density of the cold non-baryoninc matter representing 26.5% of the critical density. Despite this relatively large density, the nature of the DM remains unknown. Amongst the preferred candidates for DM are the Weakly Interacting Massive Particles (WIMPs) with a mass roughly between 10 GeV and a few TeV. An intensive search program for DM in solar system has been going on for the last decades, providing limits on the WIMP mass and cross-section, as well as hints of potential signal. The search of direct production of DM at LHC is complementary to the one performed by astrophysics experiments, providing an independent measurement. The ATLAS detector operating at LHC collected data from proton-proton collisions corresponding by now to a total integrated luminosity of 20.3 fb-1 with 8 TeV energy in the center of mass. This high energy and luminosity allows to check the validity of Standard Model and to put challenging constraints on new physics. In this talk the most recent results on DM candidates search at ATLAS will be presented. These searches are focused on WIMP, and on Lightest Supersymmetric Particle (LSP) as a DM candidate.