A secondary battery which includes a built-in charge circuit. The secondary battery includes a bare cell having a positive electrode and a negative electrode; a protection circuit section electrically connected to the bare cell; a positive electrode charge/discharge terminal and a negative electrode charge/discharge terminal electrically connected to the protection circuit section; a charge circuit section for supplying a charging current to the protection circuit section; and a positive electrode charge terminal and a negative electrode charge terminal electrically connected to the charge circuit section, wherein the charge circuit section includes a first reverse-current prevention part, and a second reverse-current prevention part for preventing damage of the first reverse-current prevention part due to the reversed charge.