Abstract: The separation of potato from soil and potato is the core of potato harvesting in China. The composition and working principle of the existing separation mechanism of potato from soil and potato are summarized in this paper, and the problems of potato harvesting and development suggestions are put forward. Aiming at the problems of unable to separate and high rate of potato damage in heavy clay soil, a reciprocating knocking combined with grid bar separation mechanism was designed, and the theoretical analysis and design calculation were carried out to determine the structure parameters, which could better solve the problem of soil potato separation. Therefore, it can promote the mechanization of potato harvest and reduce labor productivity in southwest China.