The invention provides a metal oxide arrester device for a +/-660kV DC transmission line. The metal oxide arrester device comprises an arrester body, a high-voltage terminal electrode, a low-voltage terminal electrode, an insulating base, a counter, a special connection plate, V strings of composite insulators, a clamp, an adjustable I-beam and an angle iron support, wherein the high-voltage terminal electrode is connected with a transmission conductor suspension yoke plate through the special connection plate; the low-voltage terminal electrode is fixed at one end of the arrester body and the other end of the arrester body is fixed on a transmission line tower through the insulating base, the adjustable I-beam and the angle iron support; and the middle part of the arrester body is fixed on the transmission line tower through the V strings of composite insulators. The metal oxide arrester device can meet the security transmission requirements of the +/-660kV DC transmission line in a lightning stroke state; and the disadvantages of a power failure caused by a lightning stroke are avoided.