The balloon catheter according to the present invention is one is provided with a catheter shaft having flexibility with a lumen formed inside； a balloon that is disposed at the distal end side of the catheter shaft and in communication with the lumen； a fluid regulating portion that passes a fluid that is supplied from a fluid supply source to the balloon and, simultaneous with the supply from the fluid supply source being stopped, prevents backflow of the fluid that is supplied to the balloon to the fluid supply source side； and a fluid releasing portion that releases the fluid that is supplied to the balloon to outside of the balloon.
