In recent years, the rapid growth of wine industry in China is promoting the increase of vineyards. However, the wine grapes are harvested entirely depending on hand picking in China with high cost. The old harvesting method restricts the widespread popularization and planting of wine grapes. Research on picking machine and picking mechanism of wine grapes is in its infancy in China. A study was conducted to change the artificial harvesting status of wine grapes, promote the mechanization of wine grapes thread mechanism, and establish the theoretical guidance and design basis for the picking machine of wine grapes under Chinese national conditions. In previous studies, single bunches of grapes threaded by flexible bow teeth had been certificated to be feasible. As the process of harvesting is quite complex, it needs to be studied further. Therefore, kinematic and dynamic analyses of the harvesting process were carried out to further study on threshing mechanism, and there were three factors, including rotating speed, helix angle and travel speed, which were proved to be important to harvesting. Then the walking ability test bench of indoor harvesting which could be used to study a variety of potential effective factors and new type of threshing devices was designed and orthogonal experiment was conducted. The evaluating indicators of this test were threshing rate and breakage rate, the factors of this test were rotating speed, helix angle and travel speed, and the samples of this test were the Cabernet Sauvignon. The test result showed that only rotating speed and travel speed can influence the threshing rate to a certain extent. With the increase of rotating speed from 200 r/min to 300 r/min, the threshing rate was increased from 75.7% to 92%. With the increase of travel speed, the threshing rate was decreased from 94.7% to 78%. Moreover, for the breakage rate, the effects of three factors were not significant and the breakage rate was maintained at about 20%. This study provided a reference for design and improvement of the flexible comb.