The AMS-02 detector is a wide acceptance high-energy physics experiment operating since May 2011 onboard of the International Space Station. It consists of six complementary sub-detectors providing measurement on the energy, the mass and the charge leading to an unambiguous identification of the cosmic rays. To date, 40 billion cosmic ray events have been collected. Performance of AMS in space will be overviewed as well as the first results based on data collected during the first two years of operations in space. Preliminary results on Proton, Helium fluxes and Boron-to-Carbon fluxes ratio will be presented. More details will be given on the published results on the positron fraction, individual fluxes of cosmic-ray electrons-positrons and positron anisotropy measurements.