The invention relates to an anterior cervical plate, a lifter and an internal fixation system for use in ACAF. Fusion windows are formed at a head end and a tail end of the anterior cervical plate, wherein each of the fusion windows has a width of more than 8 mm, and a height of more than 10 mm. At least one elongated lifting groove is provided at a central longitudinal axis. It further comprises an auxiliary plate which covers a front side of the plate body when in use. The lifter comprises a lifting nail and a screwdriver. The lifting nail has a first travel control body and a second travel control body. The screwdriver is provided with a screwdriver sleeve head sleeved outside of the second travel control body and making the screwdriver to rotate with it. The internal fixation system comprises the anterior cervical plate and the lifter.