Molecular　dynamics　has　been　widely　used　to　study　the　fundamental　mechanism　of　Ni-based　superalloys.　However,　the　effect　of　the　potential　function　and　strain　rate　on　mechanical　behavior　has　rarely　been　mentioned　in　the　previous　molecular　dynamics　studies.　In　the　present　work,　we　show　that　the　potential　function　of　molecular　dynamics　can　dramatically　influence　the　simulation　results　of　single　crystal　Ni-based　superalloys.　The　microstructure　and　mechanical　behavior　of　single　crystal　Ni-based　superalloys　under　four　commonly　used　potential　functions　are　systematically　compared.　A　most　suitable　potential　function　for　the　mechanical　deformation　is　critically　selected,　and　based　on　it,　the　role　of　strain　rate　on　the　mechanical　deformation　is　investigated.