To seek convenient and effective method for reconstruction of edentulous jaw, Maló and his colleagues developed All-on-Four implant immediate-function concept. The principle of All-on-Four is to support the full-arch prosthesis by 4 implants and to achieve immediate loading after surgery. Its advantages include avoiding additional bone grafting, evading critical anatomical structures and immediate prosthesis. In recent years, All-on-Four technique has been widely utilized in clinical practice as a viable approach for edentulous patients. With the auxiliary of guided surgery and biomechanical researches, All-on-Four has achieved predictable clinical results. In this paper, the development, investigation of biomechanics and main points of surgery and prosthesis of All-on-Four were briefly reviewed.