To provide a building structure with a column erected on a wall upper surface, for which level adjustment and front and back position adjustment of the column are facilitated when erecting the column, without demanding level accuracy for the wall upper surface.

In a building structure 1 according to the present invention, a level adjusting material 33 is disposed on a base material 31, height adjusting screws 53 whose lower ends are abutted to a wall upper surface 2a are screwed respectively from an upper part to a front side height adjusting part 49 and a back side height adjusting part 51 provided on the level adjusting material 33 to adjust the height to the wall upper surface 2a, and after height adjustment, the base material 31 and the level adjusting material 33 are fixed. An attaching position adjusting material 35 is provided on the level adjusting material 33, freely adjusts a position in a longitudinal direction to the level adjusting material 33 between a front side position regulation part 57 and a back side position regulation part 59, and is fixed to the level adjusting material 33 after adjusting the position in the longitudinal direction, and columns 3a and 3b and cap pieces 4a, 4b and 4c are fixed to the attaching position adjusting material 35.