When double thin-walled parts with connecting ribs are formed, the bump defects are easy to occur in the connection between ribs and thin walls. The bump defects will be more obvious with the accumulation if the control is improper, and it is easy to lead to accumulation failures. We propose a lateral lap process by equal volume method, which can obtain intersecting surfaces of ribs and walls with flat cladding morphology by controlling the starting and stopping offset in the nozzle scan path to control the lateral overlap. We also propose a power control technology based on the height detection technique to ensure that the morphology of the cladding layer in the accumulation process remains stable until the laser direct forming of the double thin-walled parts with connecting ribs is completed. The gap of the formed double thin-walled parts with connecting ribs is about 2.6 mm, and the size deviation is less than 5%. The microstructure is dense and uniform, without obvious holes, cracks and other defects, and the microhardness is 650-770 HV.