A pouch-type secondary battery comprising a lead tab, wherein the lead tab comprises: a metal plate; a plurality of concavo-convex patterns formed on a surface of the metal plate between an end and a central region of the metal plate; and an insulating film bonded to the surface of the metal plate, on which the plurality of concavo-convex patterns is located, wherein the plurality of concavo-convex patterns are formed through a surface treatment of applying predetermined laser light energy onto the surface of the metal plate, and comprise first concavo-convex patterns formed by applying the laser light energy having a first output value onto a first area of the front surface of the metal plate, and second concavo-convex patterns formed by applying the laser light energy having a second output value onto a second area of the rear surface of the metal plate, wherein the first and second concavo-convex patterns (120a, 120b) are formed so that the concavo-convex patterns adjacent to each other have a spacing of 0.001 mm to 0.5 mm, and the spacings between the concavo-convex patterns adjacent to each other gradually decrease from a central region toward either edge region in a predetermined region of the metal plate, while the depths of the concavo-convex patterns gradually increase from the central region toward the either edge region in the predetermined region of the metal plate, an area occupied by the concavo-convex patterns ranges from 10% to 95% of the entire area of the metal plate, the concavo-convex patterns are formed with a depth ranging from 1% to 80% of the thickness of the metal plate, an area occupied by the first concavo-convex patterns formed on the first area of the front surface of the metal plate is different from an area occupied by the second concavo-convex patterns formed on the second area of the rear surface of the metal plate, and an spacing between the first concavo-convex pattern is different from an spacing between the second concavo-convex pattern. a metal plate; a plurality of concavo-convex patterns formed on a surface of the metal plate between an end and a central region of the metal plate; and an insulating film bonded to the surface of the metal plate, on which the plurality of concavo-convex patterns is located, wherein the plurality of concavo-convex patterns are formed through a surface treatment of applying predetermined laser light energy onto the surface of the metal plate, and comprise first concavo-convex patterns formed by applying the laser light energy having a first output value onto a first area of the front surface of the metal plate, and second concavo-convex patterns formed by applying the laser light energy having a second output value onto a second area of the rear surface of the metal plate, wherein the first and second concavo-convex patterns (120a, 120b) are formed so that the concavo-convex patterns adjacent to each other have a spacing of 0.001 mm to 0.5 mm, and the spacings between the concavo-convex patterns adjacent to each other gradually decrease from a central region toward either edge region in a predetermined region of the metal plate, while the depths of the concavo-convex patterns gradually increase from the central region toward the either edge region in the predetermined region of the metal plate, an area occupied by the concavo-convex patterns ranges from 10% to 95% of the entire area of the metal plate, the concavo-convex patterns are formed with a depth ranging from 1% to 80% of the thickness of the metal plate, an area occupied by the first concavo-convex patterns formed on the first area of the front surface of the metal plate is different from an area occupied by the second concavo-convex patterns formed on the second area of the rear surface of the metal plate, and an spacing between the first concavo-convex pattern is different from an spacing between the second concavo-convex pattern.