A balloon catheter having a purge hole according to the present invention is configured with a duplex tube structure of an inner tube and an outer tube both of which having an opening at the distal end thereof. A balloon is provided to stretch over the section between the distal ends of the inner tube and the outer tube. A purge hole is provided on the inner tube covered by the balloon, through which the remaining air inside the balloon lumen and the balloon is discharged to a main lumen formed in the inner tube when the balloon is expanded, and which is closed by the balloon when the balloon is contracted.
