The present invention relates to a secondary battery, and in particular relating to a secondary battery in which connection between the bare cell and the protection circuit can be established by a mechanical connection system without using molding method. A secondary battery of the present invention includes a bare cell in which charging and discharging can be performed, a protection circuit substrate electrically connected to the bare cell, a substrate molding body integrally formed with the protection circuit substrate, a support member having a connection unit coupled to the substrate molding body for connecting the substrate molding body to the support member, and a connection member for connecting the substrate molding body to the connection unit.