Angle steel and steel tube have their respective advantages and The cross arm's extension length and stress of UHV tower are much more than those of ordinary tower, and the main-leg and diagonal member's stress and effective length of the cross arm are both less than those of tower, leading to the difference in UHV cross arm selection in China. In the case of the strain steel tubular tower in Anhui-to-East two-circuit UHV lines built on one tower, the selection of angle steel or steel tube was investigated for main-leg and diagonal member of the cross arm. This paper presents a selection method for cross arm, which can provids references for engineering design.