In this research, the mechanical properties of iron bicrystal, including ?5 symmetrical tilt grin boundary are calculated by simulating the nanoindentation using molecular dynamics method. In order to simulating of the process, the GPIUTMD software developed at the Faculty of Mechanics of Isfahan University of Technology was used. Nanoindentation process was simulated by a spherical indentor. The theory governing the nanoindentation process is the Hertz theory, and also a subatomic potential of the EAM type was used in order to describe the behavior and interactions of the particles of the system. In this study, simulation for rotating bicrystal was compared to the cross-sectional axis in order to better understand the disintegration of one-dimensional and boundary defects. Simulation for 12 different angles was performed and the results obtained included analytical relationships for properties such as Young's modulus and maximum shear stress and hardness of material. To obtain the Young's modulus, the Poisson coefficients were obtained at each angle based on the general-time matrix. Also, to ensure the accuracy of the analytic relationships, an angle other than the previous 12 angles was simulated and compared with the results of the analytic relationship that showed the verification of equation. Different loading zones at different angles caused a difference in values of mechanical properties. In addition, determining the radius of contact made some differences in results of two methods of solving. The results showed that in any angle, collisions with boundaries do not allow them to cross the boundary. In order to study more accurately the amount of grain boundary energy and dislocations energy, it was determined that the energy of dislocations is less than the grain boundary value. In fact, the desired boundary had Sufficient strength to prevent the passing of dislocations. Key words Molecular Dynamic, Nanoindentation, Bicrystal, Grain Boundary, Dislocations