This paper based on the interaction theory mechanism of laser-biotissue,the 2-D heat transfer model of laser-irradiated invitro human skin-tissue was established.Finite method was used to solve the numerical simulation results for temperature distribution for the Pennes′ bioheat transfer equations.Experiments about damage in invitro human skin-tissue irradiated by continuous laser are carried out.It is found that when the irradiation time reaches 6.83s,the heated evaporization is occurred.When the irradiation time reaches 11.20s,the heated carbonization is occurred.When the irradiation time reaches 25.30s,the heated combustion is occurred.The result of theoretical analysis exhibits good agreement with the experimental result.