Disclosed is a multi-function, large-scale gear milling machine, at least comprising: a milling machine body; a workbench fixedly connected to the milling machine body and arranged along the milling machine body; a flat rotary table for clamping a disc-shaped gear, wherein the flat rotary table is eccentrically embedded in the workbench and the surface of the flat rotary table is basically of equal height to the workbench; an vertical rotary table provided at one end of the workbench, a centre frame or tailstock being provided at the other end of the workbench, wherein the centre frame or tailstock has the same axis as the vertical rotary table, and the vertical rotary table cooperates with the centre frame or tailstock to clamp a shaft gear; and a fork-shaped cutter head for mounting a disc-shaped milling cutter, wherein the fork-shaped cutter head is provided on a moving base such that the fork-shaped cutter head can move in three translational degrees of freedom relative to a workpiece and an included angl