This paper is an improved version of the thesis [21]. In this paper, through comprehensive discussing relationship between the Einstein Gravitational theory and the Dirac electron theory in Riemann curved space-time, it has been found that there is a contradiction between the Einstein gravitational theory and the Dirac electron theory about the electron field energy-momentum motion. The contradiction showed that the Einstein gravitational theory can not describe the gravitational field of particles with 1/2 spin. If assuming that the Dirac electron theory is correct, we must modify the Einstein gravitational theory.