In view of the low picking rate of remaining cotton recycling device in the mechanized cotton picking field in Xinjiang, combined with the planting mode of the cotton field in Xinjiang and the operation requirements of the mechanical picking up of the remaining cotton, a kind of strap - spring tooth type residual cotton recovery device was designed. The structure and working principle of the device were described, and the operation process analysis and key parameters design of the key components of the pick-up drum were carried out. According to the design results, a prototype was trial-manufactured. Taking the picking rate of cotton leftover from the ground and cotton pick-up rate on branches as the test index, the working speed of the machine, the speed of the picking drum and the spacing of picking straps as the test factors, the three-factor and three-level Box - Behnken response surface analysis test was carried out, and the mathematical regression model between the evaluation index and the influencing factors was established by Design-Expert 10.0 software. The influence of significant factors on the evaluation indicators was analyzed, the test parameters were optimized, and the optimal parameter combination was determined to be as follows: when the machine operating speed was 0.7 m/s, the pickup roller speed was 260 r/min, and the pickup strip spacing was 120 mm, the picking rate of cotton leftover from the ground was 90.01%, and cotton pick-up rate on branches was 89.76%. All performance indicators met the design requirements.