A functional insole of a shoe having a formed body in arched form corresponding to Lisfranc's joint and medial longitudinal arch is provided to support load of the Lisfranc's joint and the medial longitudinal arch by attaching the formed body to the bottom of a top sole of the shoe and adopting a mold corresponding to the arched form of the formed body. The functional insole comprises: a top sole(1) which is prepared of natural material or synthetic resin and has length and width meeting to a foot sole; a formed body(2) which is made in an arched form corresponding to Lisfranc's joint and medial longitudinal arch and formed by integrating from heel part to Lisfranc's joint part; a mold(3) which is incorporated inside the formed body, has curvature corresponding to Lisfranc's joint and the medial longitudinal arch and a shape gradually narrowing from an upper part to a lower part of the mold in contact with the medial longitudinal arch; and a fibrous fabric layer(5) which is cut by pinking shears and adhered under the formed body at a position corresponding to the mold.
