The present invention provides a novel infusion set in which a spike (2) or a connector (12) for connection with an intravenous drip needle is covered by a cap (6, 7), arranged at which there is an opening configured so as to not allow passage therethrough of solid or liquid but so as to allow passage therethrough of gas at the interior of the cap, a hydrophobic filter (6b, 7b) being arranged at a location inward from where the tip of the spike or the connector for connection with an intravenous drip needle is inserted at the interior of the cap by way of an insertion port, and a lid (6d, 7d) at the exterior of said opening for closing said opening； and in which a three-way stopcock (5) having a primary tubing downstream branch connector (5a) equipped with a mechanism that connects in such fashion as to permit rotation about primary tubing as axis is provided； coloring optionally being applied thereto, as a result of which it is possible to carry out priming and backpriming by means of a simple operation without leakage of liquid, and it is possible to maintain stability of the infusion set and IV stand, to prevent bodily pain to patients and leakage of liquid at locations where intravenous needles are inserted, and to prevent occurrence of accidents due to human error with regard to administration procedures, and which makes it possible to easily establish standard procedures for use.
