A dental implant of the invention allows an immediate masticatory function just after being implanted in a bone structure, does not need a secondary operation, and can be effectively applied even in thin and short alveolar bone. The dental implant comprises a body portion to be inserted in the bone structure and a mounting portion integrally formed on the body portion, the body portion including a thin and short core, screw blades formed along an outer peripheral surface of the core in the shape of a wide and deep screw, and a connecting portion formed in the shape of a plurality of vertical holes and grooves and capable of containing bone growth factors. The mounting portion has a gum adhering portion to protect bone tissues and a post to be mounted with an abutment or a prosthesis thereon.