Abstract: Disclosed is an automatically openable and closable hopper set for a fruit weighing and sorting machine, wherein a hopper having two lower scale plates and a pivotally connected door is used to carry a fruit to be sorted by weight. The door is normally retained to a closed position by means of a hook portion of an arm member disposed at one side of the hopper. When the carried fruit is heavier than a set value of a weighing device passed by the hopper set, the scale plates of the hopper depress a scale rod of the weighing device, causing the hopper to descend and tilt, which further causes the arm member to shift and the hook portion to release the door from the hopper, permitting the fruit to immediately fall out of the hopper and into a collection box.