But form a fiber-reinforced resin panel having a limited width in the wide to increase the productivity and the strength, the present invention is the first step where the mold having a surface profile corresponding to the forming target wide panel prepared; A second step which is seated the first preform formed of a laminate of the reinforcing fibers along one side surface of the forming die; Is superimposed on a plurality of the surface of the other side of the two-way Z- pinning a first preform of the patch is the seating Z pin is formed by insert molding so as to project in the vertical direction on the base gusset in a thin plate shape, the lower end of each of the Z-pin wherein step 3 is inserted into the first preform; And a second preform is arranged superposed on the side portion of the upper surface of the two-way Z- pinned patch unit when the second preform doedoe secured to the surface of the forming die which is the upper end of each of the Z-pin inserted into the first preform 2 a two-way Z- pinned patch comprising the step 4 provides a wide fiber-reinforced resin panel manufacturing method.