This creation provides a quantitative dropper, including a suction ball, a tube body and an overflow prevention part. The tube system is arranged below the suction ball, the tube body includes a certain scale and a nozzle at the bottom end of the tube body； the overflow part is arranged between the suction ball and the tube body, or the tube The upper part of the body, the overflow prevention part includes a first tube neck, a second tube neck and a liquid storage bag； wherein the first tube neck is connected to the suction ball and the liquid storage bag, or to the suction The ball and the tube body； the second tube neck is connected to the liquid storage bladder and the tube body, and the second tube neck is arranged at a relative horizontal position of the maximum scale of the quantitative scale.本創作提供一種定量滴管，包含一吸球、一管體及一防溢流部。該管體係設置於該吸球之下方，該管體包含一定量刻度及一位在該管體底端的管口；該溢流部係設置於該吸球及該管體之間、或該管體之上方位置，該防溢流部包含一第一管頸、一第二管頸及一儲液囊；其中，該第一管頸係連通該吸球及該儲液囊、或連通該吸球及該管體；該第二管頸係連通該儲液囊及該管體，且該第二管頸係設置在該定量刻度之最大刻度的相對水平位置。
