A secondary battery and a method of manufacturing the secondary battery, the secondary battery including: an electrode assembly; a can to house the electrode assembly; and a cap assembly to seal an opening of the can. The cap assembly including: a cap member; a safety element disposed on the cap member; a safety vent disposed on the safety element; an insulating gasket disposed around the cap member, the safety element, and the safety vent; and a cap body to clamp the insulating gasket. A portion of the cap body is joined to the opening of the can.