Introduction The nuclear data in intermediate and high energy region have been widely used in various fields for last ten years, such as radioactive waste processing, radio therapy for cancer etc. So the measurements and evaluations of these data become more and more, these require the standard cross section in this energy region, just like already did in low energy region (≤20 MeV). In this work, the H total neutron cross section was evaluated from 20 MeV to 2 GeV, the purpose is to provide a cross section standard. Introduction The nuclear data in intermediate and high energy region have been widely used in various fields for last ten years, such as radioactive waste processing, radio therapy for cancer etc. So the measurements and evaluations of these data become more and more, these require the standard cross section in this energy region, just like already did in low energy region (≤20 MeV). In this work, the H total neutron cross section was evaluated from 20 MeV to 2 GeV, the purpose is to provide a cross section standard .