The effect of the thermal shock and thermal conduction of target irradiated by multi-pulse laser is studied. Based on the non-Fourier law and thermo-elastic theory, the non-Fourier expressions of the temperature field and the thermal stress field of target under multi-pulse laser irradiation were deduced. Taken stainless steel target as an example, thermal conduction and thermal stress equations under an appropriate boundary condition were solved by using the finite difference method. The temperature distribution and thermal stress distribution were obtained as function of time, relaxation time and location. The results show that the effect of thermal conduction of target irradiated multi-pulsed laser presents the temperature waves and the variety of temperature waves is postponed by the r