A dental implant comprises a shank and a threaded section spirally disposed on the shank. The shank includes a first section extending from a first end toward a second end of the shank and a second section connecting the first section and extending to the second end. A shank diameter of a connecting part where the first and the second sections are connected is smaller than that of the second section, whereby the subject configuration increases an implant-fastening feel of dentists and an initial implanting stability efficiently while implanting the dental implant into an alveolar bone. When the dental implant is enclosed by a growth of the bone, the second section is firmly fixed by the bone to prevent the dental implant from loosening due to an inverse torque derived from the mastication and allow it to be firmly embedded in the bone to increase the combining stability.
