PURPOSE: To reduce manufacturing time and try to reduce a cost and also provide manufacture of an outer wall panel of superior resistance.

CONSTITUTION: An outer wall panel is manufactured by providing a board 3, a frame 2 formed as nearly the same shaped frame member as the board 3, a panel member 4 shaped bigger than the board 3 and a painting sheet 6 having the same shape as the panel member 4 and bonding a painting sheet 6 over a whole plain surface of the panel member 4 and then adhering a board 3 to the other plain surface of the panel member 4 in a state forming a non adhered part 4a around this end part on which the board 3 is not adhered and also laminating and adhering the frame 2 to the board 3 and facing the non adhered part 4a of the panel member 4 to the side on which the board 3 is not adhered and bending it until it is nearly intersected at the plain surface of the panel member 4 and also bending from the other side on which a frame 2 is adhered to the board 3 so that they are placed face to face.