The flyer plate′s velocity is one key parameter during the design of laser slapper detonator.Exactly and fast estimating the flyer plate′s velocity is always the aim of initiators & pyrotechnics designers.As a result,based on laser-supported-detonation-wave theory,laser-target coupling dynamic module is build up.A new computing method of flyer plate′s velocity is put forward,which overcomes the shortcoming of using single analyzing parameter by traditional way.With the arithmetic,we analyze the influence of laser parameters（such as focus spot diameter,influence,pulse width） and flyer construction parameters（such as flyer radius,thickness） on the flyer plate′s velocity.The calculated results indicate that flyer plate′s velocity increases by degrees with the laser power density,while it increases by degrees with pulse width,focus spot diameter in local area.The flyer velocity decreases by degrees with flyer plate′s radius and thickness.