One way to improve the mechanical properties of nickel-based superalloys is by controlling the grain boundary structure, particularly the twin boundary. Understanding the role of twin boundaries in deformation can help improve the mechanical properties of nickel-based superalloys. When the twin boundary in the nickel-based superalloy increases toughness, it is used in materials such as airplane wings, and landing gear, but when it increases the yield stress, it is used in turbine blades and discs. In this study, a molecular dynamics model simulates the tensile loading process of a nickel-based superalloy containing a twin boundary under three different loading orientations.The twin boundary is oriented parallel, inclined, and perpendicular to the loading direction. The results indicate that the yield strain values are 0.0479, 0.0478, 0.0453, and 0.0501 for samples without twin boundaries, with twin boundaries parallel, inclined, and perpendicular to the loading direction, respectively. The perpendicular twin boundary has resulted in an increase in the yield strain, while the inclined twin boundary has led to a decrease in the yield strain compared to the sample without the twin boundary. Also, the ultimate strains for samples without twin boundaries, parallel, inclined, and perpendicular are 0.08061, 0.10704, 0.095, and 0.06536, respectively. The ultimate strains are in the following order: parallel, inclined, no twin boundary, and perpendicular, respectively. Crack formation and growth at the highest strain occurred at points along the twin boundary and phase interface.