In order to study the temperature field distribution of single-channel laser cladding sheet, a Gaussian heat source model was used to simulate the energy of laser beam through ANSYS software, and the temperature field of single-channel laser cladding and cooling process was simulated by using nonlinear boundary setting. A 2kW fiber laser was used to cladding iron based (Fe60) powder onto a 2mm thick T9A steel plate, and the temperature at various points was measured by a thermal imager. The results show that the simulation results of temperature field of laser cladding sheet accord with the experimental results, and the maximum error of its maximum temperature is 8.31%.The research results are useful for the optimization of laser machining parameters.