Abstract: A belt grinding machine with a belt adjusting device utilizes a screw to radially push an inclined surface of a push rod to make the push rod move axially to push rollers of the belt grinding machine, and thus the belt winding around the rollers can be adjusted. In an outer cover of the belt grinding machine is defined a penetrating hole for allowing a screw to extend out therethrough, so as to improve the safety and convenience of operation and adjustment. Moreover, the belt grinding machine is provided with an emergency switch located correspondingly to the outer cover, when the outer cover is open, it will press the emergency switch of the housing and consequently cut off the power supply, so as to further improve the safety of the belt grinding machine.