Abstract: In this paper, the three-dimensional temperature field of laser cladding is calculated through FEM. In FEM, the calculated workpiece can be divided into such elements as of different shape, size and thermal properties, so, the heat source and material conduction of laser cladding are fully embodied. In the aspect of heat source, heat flow input includes small area, high speed and uneven heat flow distribution; in the aspect of material conduction, it includes multilayer of different material and holy pre-coating. By FEM, various characteristics (surface tension, convection, mass transfer, fluid flow, metal vapor pressure etc.)are all investigated by proper processing. It has been shown that experimentally determined laser cladding pool shape is found to be in fair agreement with the corresponding theorectically calculated values. It would be possible, at least in principle, to adjust laser cladding parameters so as to achieve a desired combination of microstructure and mechnical properties.