To address the issues of high resistance and low efficiency in corn root residue excavation in cold, arid regions, a serrated double-wing blade was designed based on root distribution and mechanical properties. A mechanical model of blade-soil-root interaction was established, and EDEM simulations were conducted to optimize serration geometry and blade parameters. Optimal serration dimensions were determined as 5 mm height and 8.77 mm spacing. Through an orthogonal experiment, the best structural parameters were found to be a 23.4 degrees entry angle, 59.2 degrees wing angle, and 244.06 mm blade width. A prototype was fabricated, and field tests were performed to evaluate forward resistance and root-lifting rate under different operational settings. The optimal working conditions were a 15.5 degrees soil entry clearance angle, 130 mm excavation depth, and 5 km/h forward speed. Under these conditions, the average forward resistance was 2025.81 N, and the root-lifting rate reached 85.6%, meeting operational requirements and verifying simulation accuracy. The results provide theoretical and practical references for the design of efficient excavation tools for compost-based corn residue return in similar environments.