The invention discloses an adjustable peanut picking device.The adjustable peanut picking device comprises a driving belt transmission mechanism, a driven belt transmission mechanism, a belt wheel, a conveyor belt, a motor, a base, supports, a picking arc section, fastening components and tension wheel components.The edge of a driving belt and the edge of a driven belt are beyond the edges of the inner sides of the corresponding supports, and it is guaranteed that in the peanut picking process, interference to the motion displacement of peanut vines from top to bottom does not exist; longitudinal waist-shaped holes adjust the device to enable the device to meet the peanut picking requirements of different batches, transverse waist-shaped holes adjust the device to enable the device to be suitable for the peanut vines at different heights, and the tension wheel components adjust the relaxing state of the driving belt and the driven belt to avoid skidding, so that the device is an adjustable device; the side-looking model of an open slot of the picking arc section is a circular arc which is located on the lower left corner of a quarter circle and is opened upwards, and the picking arc section is similar to a human hand and pulls off peanuts from roots of the peanut vines, so that the device is a bionic device; the motor provides a motion drive needed by the driving belt transmission mechanism.The adjustable peanut picking device is simple in structure and convenient to operate, adopts the reliable artificial bionic principle and is convenient to adjust and beneficial for popularization in the field of agricultural machine devices.