A secondary battery including a case; an electrode assembly and electrolyte accommodated in the case; an electrode terminal electrically connected to the electrode assembly, the electrode terminal including a terminal body; a cap plate sealing the case, the terminal body penetrating through the cap plate; and a seal gasket surrounding a lower portion of the terminal body, wherein the electrode terminal includes a laterally protruding part on a portion of the terminal body protruding outside the case, and the seal gasket is in close contact with a lower end of the protruding part.