A composite material structure that can be made lighter in weight is provided, with the stress concentration at peripheral edge regions around holes being taken into consideration. A wing (1) that is a composite material structure is of a composite material that extends in one direction, has access holes (5) formed therein, and is made of fiber reinforced plastic. A lower surface outer plate (3) of the wing (1) is subjected to a tensile load in the longitudinal direction. The longitudinal tensile stiffness of peripheral edge regions (3a) around the access holes (5) is lower than the longitudinal tensile stiffness of other regions (3b) surrounding the peripheral edge regions (3a).