Disclosed is a shoe sole capable of horizontally maintaining an inner bottom section of footwear when the user walks. The shoe sole includes an outsole provided at front and rear portions thereof with a plurality of protrusions, a mid-sole stacked on the upper surface of the outsole and formed with a plurality of perforation holes, an insert provided at a bottom surface thereof with a plurality of protrusions, which are inserted into the outer wheels by passing through the perforation holes of the mid-sole, and a lasting board stacked on an upper surface of the insert coupled with the mid-sole. The inner bottom section of footwear is horizontally maintained. The shoe sole attenuates foot fatigue and provides comfortable wearing feeling when the user walks on an unpaved road or climbs a mountain.