Laser drilling technology is a new feasible and developing method of rock destruction. The unified modeling method of laser and rock interaction is a complicated subject of heat transfer science. According to the energy conservation law, the fundamental equation of heat transfer is established. Some primary parameters such as enthalpy, thermal conductivity and specific heat are simplified respectively on the liquid-gas interface or the liquid-solid interface. The general mathematical model of temperature fields on laser drilling process is proposed. Using the Galerkin method, the numerical investigation of a practical example in laser drilling rock is analyzed.