The invention relates to a bundling instrument, in particular to a straw bundling instrument. According to the straw bundling instrument, a bandage can be fixed, straw can be bundled conveniently, thelabor cost is reduced, and the situation that the knotting is affected due to loosening of the bandage is avoided. According to the technical scheme, the straw bundling instrument comprises a frame body, a supporting plate, a round frame, a handle, a rotating shaft, clamping blocks, a casing pipe, a disc, a ratchet wheel, a rocker, a supporting rod, a guide sleeve, a clamping rod, a threaded disc, a first bearing seat and the like; the round frame is fixedly connected to the right side of the frame body, the circle center of the round frame is fixedly connected with the first bearing seat inan embedded mode, and the rotating shaft is connected with a bearing in the first bearing seat. According to the straw bundling instrument, the bandage winds the casing pipe, and the handle is held, so that the bandage can be pulled to bundle the straw; and the binding head end is fixed through the device, the rocker is rocked and reversely rotated to enable the straw to be bundled, and the strawcan be clamped through a pressing device, so that an operator can better bundle the straw.