This paper has combined temperature measuring and numerical simulation to research the laser and tissue photo-thermal effect.Two dimensions finite elment method was used to solve the bio-heat transfer equation and the tissue simulation temperatures were computed.Temperature measuring can be used to verify the therory model.Miniature thermocouple and infrared radiation thermometer were used to monitor the inner and surface bio-tissue temperature synchronously,which is suitable to minimally invasive and rapid minute point tissue temperature measuring.The experiment results of CO_2laser coagulated in vivo mouse skin experiments and numerical simulation results showed the temperature response curve shape were almost accordant,the surface irradiation point(r=0 mm,z=0 mm) and the subcutaneous(r=0 mm,z=1 mm) temperature peak value relative error was around 23.24% and 0.4% respectively.Perfusion rate and position were the main influence factor of temperature curve,therefore exact tissue parameters and more precise orientation can further decrease the error and provide straight,complete and predictive information for the laser therapy.