A secondary battery includes, in a battery case, an electrode body having an electrode sheet, a current collecting member including a weld part ultrasonic welded to a current collecting foil of the electrode sheet, and a pressure-type current interrupt mechanism electrically connected to the current collecting member. The current interrupt mechanism has a first valve element integrated with the current collecting member and a second element body, both joined at a joint portion. Of the current collecting member, the first valve element, and the second valve element, at least a part between the weld part and the joint portion is made of damping metal. A method of manufacturing this secondary battery includes: a step of forming a structure in which the first and second valve elements are joined at the joint portion; and a step of thereafter ultrasonic welding the current collecting foil and the weld part.