A round tower foot plate for a +/- 800kV ultra high voltage direct current line is characterized in that vertical plates are arranged on a round base plate and distributed at intervals from the center to the edge of the base plate, and reinforcing ribs are welded between the vertical plates to support the vertical plates. By means of analysis and research on iron tower feet, the round tower foot plate is provided to overcome the shortcomings of the existing common square tower foot plate. The base plate adopts round distribution, the vertical plates are evenly filled at intervals, collision of foundation bolts and the vertical plates is avoided, machining is simple, the structure is symmetrical, the isotropy is achieved, and stress eccentricity is reduced. Compared with the common square tower foot plate, the round tower foot plate is direct in force transfer and stable in stress, the base plate is small in thickness, the economy is remarkable, and machining convenience is improved. The round tower foot plate is applicable to power transmission lines of various voltage grades of self erecting iron towers like direct current ultra high voltage or large span iron towers.