The present invention relates to a drill bit structure which comprises a body. The body has a free end, an intermediate section and a connection end. The body comprises a first groove portion, a second groove portion, a third groove portion, a fourth groove portion and a fifth groove portion. The first groove portion is partially overlapped with the third groove portion from the free end. The second groove portion is partially overlapped with the fourth groove portion from the free end. After extending a preset axial distance from the free end, the first groove portion and the second groove portion are partially overlapped with each other by forming an intersecting protrusion. The fifth groove portion is extended from the intermediate section toward the connection end. The first, second, third and fourth groove portions are extended to the fifth groove portion.