The utility model provides a throttling body fluid drainage tube. One end of the drainage tube is provided with an internal thread connection port, and the internal thread connection port is connected with an external thread connection port of a remaining needle. The drainage tube is connected with a dropper on the back side of the internal thread connection port and provided with an adjuster on the back side of the dropper. The throttling body fluid drainage tube is connected with the external thread connection port of the remaining needle in a threaded mode, and therefore a conical connector of the body fluid drainage tube can be inserted into an inner hole in the tail end of the drainage tube. The drainage tube is provided with the dropper, and therefore the flow speed of body fluid can be conveniently observed according to the dripping speed of liquid drops. The drainage tube is provided with the adjuster adjusting the releasing speed of the body fluid, and therefore the phenomenon that various complications are caused by the excessively high flow speed of the body fluid is avoided, and the medical risk of patients is lowered.