Abstract: In order to get simulation teeth of ring sprockets with variable cross-section by means of laser cladding direct manu facturing technology, experiments were made based on inside-laser powder feeding technology and motion control of KUKA robot. According to the optimized process parameters, the scanning paths were planed and the lift amount of each layer was accurately controlled based on the incremental method of extra height and extra length. The substrate was preheated and the detection of dimension and microstructure of the formed tooth was made. The problem of edge collapse in the forming of irregular-section parts was solved. The machining allowance was controlled preferably on the basis of promising the sufficient size in different sections. And the cracking and spalling of cladding layer was avoided. The irregular-section tooth was successfully made on 42CrMoV substrate. The results indicate that the powder utilization rate is more than 60% in the processing. The surface of the part was smooth with no powder adhered. The size of the entity was within reasonable limits. The teeth and the substrate formed good metallurgical combination. The microstructure was uniform without microcracks and the microhardness was uniform in every section.