A venting device inserted into a sealing part of a pouch of a secondary battery according to an embodiment of the present invention includes: a housing inserted between confronting surfaces of the sealing part so as to be sealed together with the sealing part, the housing being made from a metal plate; a gasket made of a polymer and disposed in the housing and through which a passage is defined providing gas communication between an inside and an outside of the pouch; and a plate spring made of a metal, the plate spring being disposed in the housing and assembled with the gasket, the plate spring being configured to open and close the passage in response to a change in an internal pressure of the pouch, wherein the housing includes a crimping part crimped together with the gasket on an upper end of the housing.