An antibacterial electric charge generation yarn meets requirements (a) to (e) mentioned below simultaneously and suppresses proliferation of bacteria by electric charge generated upon deformation of the yarn: (a) a main component of the yarn is polylactic acid; (b) the yarn is twisted; (c) the yarn has a double torque of 50 T/50 cm or less; (d) the yarn has a single fiber fineness of 0.05 to 5 dtex; and (e) the number of filaments in the yarn is 10 to 400.