Abstract: Disclosed is a connection structure for an IV tube of an IV infusion set, in which an IV tube is firmly connected by fitting using a connector without using an adhesive, thereby preventing bacterial infection. The connection structure is configured such that an outlet provided in an IV bag is connected to a drip chamber, the IV tube is connected to the drip chamber to allow an IV fluid to flow, an end of the IV tube is connected to an injection site for injecting the IV fluid, wherein a connector is provided on an outer circumferential surface of the IV tube that is connected to the drip chamber and the injection site, thereby locking the IV tube.