The present invention is a lead outlet structure of a secondary battery in sheet type, which comprises; an internal electrode pair in sheet type which is obtained by stacking alternately sheets of cathode electrode and sheets of anode electrode with separator between them, a flexible envelope form package that contains inside hermetically this internal electrode pair and electrolyte, a pair of internal leads that are respectively connected with separately each of cathode electrode and each of anode electrode of the internal electrode pair inside the envelope form package, a pair of external leads that are provided on the outside of the above-mentioned envelope form package corresponding to each of the above-mentioned internal leads with the above-mentioned envelope form package in between, and a pair of connecting means, one side of which is connected to each of the internal leads inside the above-mentioned envelope form package and the other side is connected to each of the external leads on the outside of the envelope form package as well so that each of the internal leads and each of the external leads are electrically connected, and which is light, thin and flexible, and is capable to be a compact and light weight product and can attain a relatively large capacity secondary battery.