PURPOSE: To largely improve resistivity against shearing stress by applying tension to anchor bolts that are made to penetrate into a hollow, box-shaped column base metal body, and by dispersedly transmitting the tension to the whole area of bearing surface of a concrete foundation.

CONSTITUTION: A hollow, box-shaped column base metal body 2, made of cast iron with its upper side opened, is formed of a bottom board 5 to which anchor bolt holes 9 and 9 are bored, a protruding part 7 that is provided thereon and ribs 6, 6 and 8. A steel column base 15 is connected by butt welding to the protruding part 7 of the column base metal body 2 and the anchor bolt holes 9 and 9 of the base board 5 are penetrated with anchor bolts 17 and 17 planted to a concrete foundation 16. Then upper steel plates 3 and 3 are fit to the anchor bolts 17 and 17 being supported with the upper ends of the ribs 6, 6 and 8, and tension is applied to the anchor bolts 17 and 17. With the dispersedly transmitted to the bearing surface of the concrete foundation through the upper steel plates 3 and 3, ribs 6, 6 and 8 and the bottom board 5, the steel column base 15 is tightly connected to the concrete foundation.