Grid array electronic component, wiring-strengthening method and producing method wherein a grid array electronic component in which a grid array LSI chip 2 having a large number of lands 3 connected to a large number of lands 13 through connecting means 30, the lands 13 are connected to a wire 4 of a printed wiring board 1, an auxiliary land 5 is formed at a connection portion 31 of the lands 13 on the printed wiring board 1 corresponding to the lands 3 of a corner portion of the grid array LSI chip 2 connecting the wire 4 and the concentration of stress of the connection portion 31 is moderated, thereby providing the effect that the brake of the wire in the connection portion 31 is prevented.