A method for manufacturing a multi-piece board having a frame section and a multiple piece sections connected to the frame section includes forming a frame section from a manufacturing panel for the frame section, sorting out multiple acceptable piece sections by inspecting quality of piece sections, forming notch portions in the frame section and the acceptable piece sections such that the notch portions allow the acceptable piece sections to be arranged with respect to the frame section, provisionally fixing the piece sections and the frame section in respective positions, injecting an adhesive agent into cavities formed by the notch portions when the frame section and the piece sections are provisionally fixed to each other, and joining the acceptable piece sections with the frame section by curing the adhesive agent injected into the cavities.