Sampling device of grassland plant roots

The invention discloses a sampling device of grassland plant roots. The sampling device comprises a ring tool, a tray and a traction mechanism used for pushing the tray into the ring tool. The ring tool is a hollow cylinder; the bottom of the ring tool is provided with a serrated blade; the top edge of the ring tool is provided with fasteners; the tray comprises a tray body and a fixing socket arranged on the surface of the tray body; the tray body can move in the ring tool along its axis; the traction mechanism comprises a transverse bar, a rotating bar, a sliding sleeve and hooks. The traditional way in which an undisturbed soil sample is ejected out of the ring tool is changed, the disturbance of a jack upon the undisturbed soil sample in the ring tool is avoided, human error is reduced, completeness of plant roots is ensured, sample acquisition precision is improved, field work efficiency is improved, and time and labor consumption is reduced.