A pouch for a secondary battery, the pouch comprising: an upper housing module having a can-type structure which includes a metallic base plate having a concave-shaped accommodation space, and a polymer layer (111, 112) formed on one surface or both surfaces of the metallic base plate; and a lower pouch sheet which is combined with a lower surface of the upper housing module to seal the accommodation space, the upper housing module further comprises integrated lead tabs (113a, 113b) in which tabs, which are respectively connectable to electrodes of an electrode assembly that is accommodated in the accommodation space, are formed as an integrated structure, characterized in that the polymer layer (111, 112) is a reinforcing layer comprising: a first reinforcing layer which is formed of a material selected from the group consisting of cast polypropylene, urethane, polyethylene terephthalate, polyimide, Nylon, and a combination thereof on an outer surface of the metallic base plate, that is the opposite side of the accommodation space with respect to the accommodation space of the metallic base plate; a second reinforcing layer which is formed in a structure in which one or more layers of a material selected from the group consisting of polyethylene, polypropylene, and a combination thereof are stacked on an inner surface of the base plate facing the accommodation space, the upper housing module has a thickness in a range of 0.2 mm to 0.5 mm, the lower pouch sheet has a thickness in a range of 150 μm to 180 μm, the metallic base plate has a thickness in a range of 0.12 mm to 0.3 mm. an upper housing module having a can-type structure which includes a metallic base plate having a concave-shaped accommodation space, and a polymer layer (111, 112) formed on one surface or both surfaces of the metallic base plate; and a lower pouch sheet which is combined with a lower surface of the upper housing module to seal the accommodation space, the upper housing module further comprises integrated lead tabs (113a, 113b) in which tabs, which are respectively connectable to electrodes of an electrode assembly that is accommodated in the accommodation space, are formed as an integrated structure, characterized in that the polymer layer (111, 112) is a reinforcing layer comprising: a first reinforcing layer which is formed of a material selected from the group consisting of cast polypropylene, urethane, polyethylene terephthalate, polyimide, Nylon, and a combination thereof on an outer surface of the metallic base plate, that is the opposite side of the accommodation space with respect to the accommodation space of the metallic base plate; a second reinforcing layer which is formed in a structure in which one or more layers of a material selected from the group consisting of polyethylene, polypropylene, and a combination thereof are stacked on an inner surface of the base plate facing the accommodation space, the upper housing module has a thickness in a range of 0.2 mm to 0.5 mm, the lower pouch sheet has a thickness in a range of 150 μm to 180 μm, the metallic base plate has a thickness in a range of 0.12 mm to 0.3 mm. a first reinforcing layer which is formed of a material selected from the group consisting of cast polypropylene, urethane, polyethylene terephthalate, polyimide, Nylon, and a combination thereof on an outer surface of the metallic base plate, that is the opposite side of the accommodation space with respect to the accommodation space of the metallic base plate; a second reinforcing layer which is formed in a structure in which one or more layers of a material selected from the group consisting of polyethylene, polypropylene, and a combination thereof are stacked on an inner surface of the base plate facing the accommodation space, the upper housing module has a thickness in a range of 0.2 mm to 0.5 mm, the lower pouch sheet has a thickness in a range of 150 μm to 180 μm, the metallic base plate has a thickness in a range of 0.12 mm to 0.3 mm.