1. A laser marking machine, wherein the laser marking machine comprises: a control main board, a laser device and a galvanometer, the laser device and the galvanometer being connected to the control main board, respectively; the galvanometer being configured to move at a predetermined moving speed on the basis of coordinate of target image pixel dot; the laser device being configured to output laser; the laser marking machine further comprises: a first receiving module at the control main board, configured to receive coordinate of the target image pixel dot and gray scale value of the target image pixel dot; a first calculation module at the control main board, configured to calculate output power of the target image pixel dot by using the gray scale value; and a control module at the control main board, configured to control the laser device to use corresponding output power according to displacement of the galvanometer, and to output laser specific to each target image pixel dot.