Basded on the hollow laser beam internal powder feeding technology, the thickness-variable eccentric ring structure is fabricated by laser cladding forming. The scanning paths for forming the thickness-variable eccentric ring structures are planned. The layer-height control software based on machine vision is used to obtain the actual height for the each forming layer, which is compared with the desired height. The speed-correction model based on the proportion-integration (PI) controller is established. The forming eccentric ring structure has the minimum wall thickness of 2.14 mm and the maximum wall thickness of 6.38 mm. The error of actual total height with respect to the desired one of each segment is relatively small and the overall height is relatively flat, which shows the forming accuracy is high. At positions with different wall thicknesses of forming parts, the grain structure is uniform and grain size is comparable.