Abstract: This paper presents a novel conception that intense relativstic electron beam is accelerated by compact electrostatic accelerator cube. According to the theoretic analysis and PIC, the electron beam with current 1 kA and initial voltage 500 kV is accelerated in the accelerator of 0.8 m and it becomes 10 MeV. The beam is transported and accelerated without focusing magnetic field. The biggest electronic field can be decreased 20 MV/m by optimization design.