The work aims to deposit stellite6 alloy coating on 45# steel sheet by virtue of laser cladding and study performance of the coating. Microstructure and morphological characteristics of the coating before and after heat treatment were analyzed by Olympus optical microscope. Mechanical property of the coating was studied by HV-1000B microhardness tester. Compared with the coating without heat treatment, dendrites and cellular crystals in structure of the coating subject to heat treatment reduced significantly while isometric crystals increased. Meanwhile, grain growth, uniform distribution of alloying elements as well as hardness in horizontal and vertical directions decreased to varying degrees. Average microhardness in horizontal and vertical directions of the coating subject to solution treatment was HV350 and HV490 respectively; for that of the coating without solution treatment, HV520 and HV556 respectively. The hardness decreased while the structure was more uniformly distributed, and plasticity and comprehensive performance both increased. The application of heat treatment process to coating preparing and follow-up treatment has changed the mode of improving coating performance by simply relying on deposition parameters. Heat treatment is another way to improve the comprehensive performance of the Stellite6 alloy coating.