A contrast agent removing device configured to remove a contrast agent from blood vessels includes: an elongated outer tube 40; an inner tube 20 arranged in an interior of the outer tube 40; an expandable portion 30 interlocked with a distal portion of the inner tube 20 and configured to be capable of being stored within the outer tube 40 and to expand radially outward in a funnel shape opening in a distal direction by projecting from the outer tube in the distal direction; and a fixing portion 80 provided at the rim of the expandable portion 30 and configured to be capable of being fixed to a contact object.