The utility model discloses a tobacco soil covering machine with an automatic dust guard plate regulating device. The tobacco soil covering machine comprises a rack, wherein the bottom of the front end of the rack is provided with driving wheels, and two sides of the upper part of the front end of the rack are respectively provided with a dustproof device; the upper part of the rack is also provided with a power driving device comprising a diesel engine and a speed reducing mechanism; the power output end of the diesel engine is connected to the driving wheels through the speed reducing mechanism; the bottom of the rear end of the rack is provided with a roller plough which is connected to the speed reducing mechanism through a conveyor; the dustproof devices are automatically adjusted and are divided into two groups, and the two groups of automatically-adjusted dustproof devices are respectively and correspondingly hinged to two sides of the front end of a frame, each group of automatically-adjusted dustproof devices comprises two dust guard plates, namely a first dust guard plate and a second dust guard plate, and an automatic dust guard plate driving structure, and the first dust guard plate and the second dust guard plate are hinged with each other. The tobacco soil covering machine is capable of realizing the automatic adjustment of the dust guard plates without stopping, and is simple and convenient to operate.