A female terminal includes a box portion which is formed into a quadrangular prism-like shape so as for a tab of a male terminal to fit therein by bending a copper alloy plate which is obtained by being continuously and repeatedly bent before an age heat treatment is applied thereto, which has a proof stress of 700 MPa or larger and a width of 10 mm or larger and in which no crack is produced therein when bent 180 degrees about a bending axis which is at right angle to a rolling direction of the copper alloy plate. The box portion comprises notches which are formed in inner sides of bent portions produced by bending the copper alloy plate. A depth of the notch is set to be in the range from ¼ to ½ of a thickness of the copper alloy plate.