A top drive system of a CNC milling and grinding brick machine, which is to install a vertical rail bracket above the workbench of the CNC milling and milling machine, a horizontal rail bracket is connected to the vertical rail bracket, and an upper servo motor is installed on the top of the vertical rail bracket to work At the same time, the upper servo motor drives the main gear box to run through the main drive shaft, and the main gear box drives the left gear box and the right gear box through the left drive shaft and the right drive shaft respectively. When the gearbox is running, it drives the milling and grinding brick machine to process the bricks.