This paper proposes a novel atomistic-continuum mechanics (ACM) based on the finite element method (FEM) to investigate the mechanical bulk behavior of atomic-level single crystal silicon under uniaxial tensile loading. The ACM could be reduced efficiently the computational time and maintained the simulation accuracy. A general form of Stillinger-Weber potential function was used for interaction between the silicon atoms in the ACM simulations. Simulation results shows that the Young’s modulus of single crystal silicon were 121.8, 153 and 174.6 GPa along the (100), (110) and (111) crystallographic plane, respectively. These results are in reasonable agreement with the experiment and simulation results reported in the literature.