300mm。The structural principle of zigzag scraper transportation device in combine machinery for field cleaning and land preparation operations, which is used for remnant plastic film, stubble and soil, was studied. Meanwhile, the resistance, the energy consumption and power were analyzed. An optimization mathematical model was established for the pursuit of minimal energy consumption. The optimization results including the length of scraper 890mm, the width 260mm, the distance 500mm, the working speed 2.5m/s and the working obliquity 33°were obtained by calculation. Finally, the results were validated by experiment. The optimal distance between the first scrapers and loosening shovels was 300mm.  