In order to study the key factors affecting the extraction force of white radish, an extraction device for white radish was designed. The device was driven by DC motor, and was designed to pull white radish leaves using a gripper connected to a wire rope. The peak value and duration of extraction force were recorded by computer. ‘Jixiamei 50’ white radish was used as test material, the extraction force of white radish was analyzed in this study. The extraction line speed, extraction angle and clip height of white radish extraction device and soil moisture content were determined as test factors, and the extraction force peak value of white radish was determined as test index. Single factor and response surface tests were carried out to explore the influence of each test factor on the extraction force peak value of white radish. Then, the optimum working parameters of the extraction device for white radish were determined to be the clip height of 1 cm, the extraction line speed of 0.03 m/s, the extraction angle of 35°, and the soil moisture content of 21.63%. With these conditions, the extraction force of white radish was the minimum, and the extraction force peak value was 52.5 N, which had a good fit with the prediction results of the extraction force peak value of white radish.