Disclosed is a dry carbon dioxide capture apparatus with improved carbon dioxide capture efficiency through preventing gas backflows into vertical transport lines. The dry CO2 capture apparatus includes a capture reactor having a capture buffer chamber on the bottom side, a capture diffusion plate on top of the capture buffer chamber, and adsorbent particles in a space above the capture diffusion plate; a first separator connected to the capture reactor through a vertical transport line; a regenerator having a regeneration buffer chamber on the bottom side, a regenerating diffusion plate on top of the regeneration buffer chamber, and adsorbent particles in a space above the regenerating diffusion plate; a second separator connected to the regenerator through a gas separation line; and a second particle transfer line connected to the regenerator at one end and connected to the capture reactor at the other end.