Nucleation plays a key role in the cryogenic field, such as supersonic separator, wind tunnel design, and two-phase turbo-expander. However, a lack of accurate knowledge on intermolecular potentials and uncertainties in some key physical properties make it difficult to understand the nucleation mechanism. In this paper, molecular dynamics (MD) simulation is conducted to investigate the micro-scale process of cryogenic gas nucleation at high supersaturation. The Lennard-Jones potential model is used to describe interactions between particles and the Newton equation of motion is solved via Velocity-Verlet method. Based on simulated microscopic quantities, nucleation rate and Wilson point are calculated, and compared with the results from classical nucleation theory. The influences of the supersaturation on the nucleation process also are explored, both of which determine the onset of nucleation and generation rate of cluster.