A composite material structure reinforced against stress concentration in peripheral edge portions of holes and enabled to be reduced in weight. A wing (1) is formed in a box structure. A lower surface outer plate (3) of the wing (1) includes: a center section (3b) made of metal extending in one direction and having access holes (5) formed therein; a front section (3a); and a rear section (3c) made of fiber reinforced plastics extending in the one direction and connected to both side portions of the center section (3b). As the metal used for the center section (3b), a titanium alloy or an aluminum alloy is suitable.