To provide a female terminal in which the strength of an electrical contact portion of a tubular shape having a rectangular cross-section is enhanced, thereby preventing the terminal from being deformed during the manufacture of the terminal. In the female terminal, ears of a contact spring piece, provided within the electrical contact portion of a tubular shape having a rectangular cross-section, are engaged respectively in window holes formed respectively in side walls of the electrical contact portion. Elongate reinforcement projections or reinforcement grooves subjected to work hardening are provided at the side walls of the electrical contact portion, and extend in a direction of the height of the side walls, the projections or the grooves being provided on opposite sides of each of the window holes, respectively.