The invention provides a four-column automatic printing machine for aluminum substrates, including an automatic feeding system, an automatic printing system, and an automatic discharging system, wherein the automatic feeding system transmits the aluminum plate through a conveyor belt; the automatic printing system includes a printing screen, a screen frame, Scraper, nozzle, workbench, automatic lifting column, automatic printing system to print thermally conductive insulating colloid evenly on the aluminum plate; the output system transfers the aluminum plate with a dense and uniform insulating layer printed on the surface through the conveyor belt for output, and the screen printing In the system, the workbench is supported by four automatic lifting columns, and the surface of the workbench is laid with horizontal sliding electric guide rails; it also includes a height sensor, a scraper moving rod, a rotating head, and the rotating head is connected to the scraper moving rod and the scraper; the height sensor is installed on the grid Below the frame; workbench, scraper moving rod, nozzle, positioning sensor, and height sensor are all connected to the main console for control. The invention has the characteristics of automatic feeding, automatic positioning and calibration, automatic printing and high production capacity.