To provide anchor bolts evenly projecting from a foundation concrete.

An anchor bolt for a sill is embedded in a concrete foundation C at the lower part thereof to pierce a sill M put on the concrete foundation. And a fastening nut 2 is screwed with the upper end of the bolt to fix the sill on the foundation. The anchor bolt body 1 provided with a male screw 3 connected to the fastening nut at the upper end, is partly bent spirally to form a ring 4 provided with an inserting space for a rod. A horizontal rod (a) is arranged in the inside of the ring 4 through the insertion space.