Cylindrical secondary battery

The present invention relates to a cylindrical secondary battery comprising: an electrode assembly provided with an electrode tab; a battery can which accommodates the electrode assembly through an open part formed on one side; a cover plate covering the open portion; a collector plate disposed between the electrode assembly and the cap plate and electrically connecting the electrode tab and the battery can; and the spacer comprises a main body part positioned between the collector plate and the cover plate, a sealing part for sealing the space between the battery can and the cover plate, and a connecting part for connecting the main body part and the sealing part. The collector plate may include: a central portion; a tab coupling part that expands outward from the central part and is coupled to the electrode tab; a can coupling part coupled to the battery can and having a height difference from the tab coupling part; and a bridge portion connecting the center portion and the can coupling portion, and extendi