By using the relationship between the linear velocity and the angular velocity on the same ellipsoid, a three-bar three-point mechanism is designed. And by using the single chip microcomputer to control the whole process of removing the core, the speed control of removing the core of jujube is realized. At the same time, it also realizes the automatic positioning, automatic de-nucleation and automatic discharging in the process of de-nucleation. The test prototype shows, the device can meet the needs of current automatic operation of jujube enucleation, with the advantages of simple construction, accurate location, high efficiency, easy operation etc.