The excellent mechanical properties of nickel base single crystal superalloy are mainly due to its ordered L12 structure γ? (Ni₃Al). In order to study the effect of laser shock γ?, the molecular dynamics model of single crystal Ni₃Al was constructed by molecular dynamics method, and the microstructure evolution behaviors of [100], [110] and [111] were analyzed. The results show that the plastic deformation mechanism of [100] crystal shock is the transformation from FCC phase to BCC phase, and the content of BCC phase increases with the increase of shock pressure; The plastic deformation mechanism of [110] and [111] crystal direction shock is dislocation slip, and the [110] crystal direction slip system is mainly (1)[011] and (11)[01], The [111] crystal slip system is mainly (1)[10] and (11)[101],the dislocations produced are mainly 1/6<112>(Shockley). However, with the increase of impact pressure, the plastic deformation mechanism is the transformation from FCC phase to BCC phase, and disordered structure is produced at the same time.