Controlling and optimizing the local remanufactured multilayer stereo forming microstructures of K418 thin-walled blades is a difficult task. This study investigates a laser-based remanufacturing coating process and microstructure control of K414 alloy. The alloy is coated with Inconel 718. The formation of Inconel 718 is tested by three processes, which are used for observing the microstructure of the coating, testing mechanical properties, and then comparing, analyzing, and conducting a single-channel multilayer stereo forming test. According to the test results, the optimal coating parameters are as follows: laser power is 1.2 kW, scanning speed is 300 mm/min, powder feeding rate is 25 g/min, gas flow rate is 3 L/min, pulse width is 10 ms, and duty ratio is 1∶1. The matrix combining with a single coating forms a strong metallurgical bonding with height of 1.537 mm and width of 1.414 mm. The coating mainly consists of fine and dense equiaxed crystal dendrites, oriented columnar dendrites, and cell crystals. The microhardness of the coating is 263.7-289.7 HV_0.2. The total height of a multi-layer three-dimensional formation is 3.67 mm with a microhardness range of 284.3-315.5 HV_0.2. The bottom layer is coated with Laves, MC, and γ'' phases. The hardness of the bottom layer is increased by the dispersion-strengthened alloy.