Abstract: In response to issues such as high flax damage rate and poor root difference uniformity during working process of self-propelled flax puller's cutting platform in China, structural optimization design was implemented for components including frame weldment, flax pulling mechanism, conveying mechanism, and tensioning mechanism．Technical parameters included cutting platform width of 1452 mm, a flax picking stroke of 150 mm, and a clamping picking area with a horizontal direction at 75° angle．Relationship between flax-pulling line speed ν₁ and forward speed ν₀ was clarified as ν₁=1.56 ν₀, and theoretical root difference was reduced from 51 mm to 44 mm．Field trials showed that cutting platform flax rate of 2.3%, a missing picking rate of 0.6%, and a coefficient of variation for root difference uniformity of 4.1%．Compared to industry standards, flax damage rate decreased by 2.7 percentage points, variation coefficient of neatness of hemp roots decreased by 0.9 percentage points, and missed-pulling rate decreased by 0.4 percentage points．A reference for performance improvement of self-propelled flax puller was provided．