PURPOSE: To minimize the installation space with less wastefulness and a high operating efficiency by an elliptic plane circulation structure, and provide high sorting by effectively-preventing a vegetable from jumping out at a circular track part due to the features of the structure without damaging the surface of the vegetable.

CONSTITUTION: A cucumber sorting machine is provided with an elliptic conveyer which transfers a plurality of trays 7, a cucumber receiving part and an image processing part which recognizes its shape at one straight track part, and a sorting part which sorts the cucumbers according to the length and shape at the other straight track part. A jumping-out prevention device F which prevents the cucumbers placed on the tray 7 in a circular track part between the image processing part and the sorting part from being jumped out by centrifugal force is moved on the circular track part together with the tray 7, and a cover member 48 which can press vegetable from the above is mounted on a sprocket 46 through a supporting arm 49. At a return part to the final end of the image processing part from the starting end of the sorting part, there is also provided a guide rail 51 which lifts up the cover member 48 in the air.