The present invention provides a carbon dioxide external administration device according to which assured cosmetic and medical effects can be readily obtained. This administration device comprises a sealing enclosure member capable of sealing a body surface from the outside air, a supply means for supplying carbon dioxide into the inside of the sealing enclosure member, and an absorption aid that assists transdermal or transmucosal absorption of the carbon dioxide inside the sealing enclosure member. The administration device may further have a carbon dioxide amount indicator that expands upon carbon dioxide being supplied into the sealing enclosure member, and contracts by the decrease of carbon dioxide.