A blood vessel embolization method includes inserting a balloon catheter into a blood vessel of a human or an animal having a lesion site and disposing a balloon of the balloon catheter at a portion located at a proximal side of the blood vessel and in a neighborhood of the lesion site thereof shutting off a blood flow in the blood vessel by expanding the balloon discharging a glucose solution from a distal end of the balloon catheter in a state in which the blood flow in the blood vessel is shut off discharging a cyanoacrylate-based embolization substance-containing liquid from the distal end of the balloon catheter after the glucose solution injection step hardening an embolization substance by maintaining a blood flow shut-off state of the blood vessel after the embolization substance injection step and removing the balloon catheter from the blood vessel after the embolization substance-hardening step.
