Oilseed-vegetable-dual-purpose is the technology increasing to harvest shoot on the premise of rapeseed, as fresh vegetable, can effectively improve the benefit of rape. However, manual harvesting is inefficient and costly, and lacking of mechanized harvesting technology and equipment. Therefore, a mechanized row harvesting process plan was proposed, which included reciprocating cutting, clamping-transporting, throwing-placing, cross transporting and collecting. Further, a self-propelled six-row harvester was developed on the basis of the agronomic and mechanized harvesting requirements of oilseed rape shoot. The structure and working principle of the harvester were elaborated, and the key components such as cutting device, clamping and conveying device and cross transporting device were designed based on the theoretical analysis. In addition, the main structural and working parameters of the harvester were determined based on the geometric and kinematic conditions of the oilseed rape shoot migration along the transporting path.Field test results showed that when the speed ratio coefficient of the cutter machine and the harvester was 0.8, the clamping-transporting speed was 0.37m/s, the speed of the cross belt was 0.5m/s, the success rate of cutting was 100%, during the harvesting operation, and the clamping-transporting success rate was 93.69%, the operation damage rate was 7.4%, and the rate of production was 0.17hm2/h;moreover, the key components of the harvester operated stably, and the harvester can complete the processes such as cutting, clamping-transporting, cross transporting and colleting at one time, and performance indicators met the requirements for mechanized harvesting for oilseed rape shoot. The research results can provide ways for the design and improvement of mechanized harvesting equipment for stem and leafy vegetables.