The invention discloses a fertilizer application machine capable of burning forage into a plant ash fertilizer. The fertilizer application machine comprises a sliding table, wherein a material inlet pipe is inserted into and penetrates through one end of the sliding table, the upper end of the material inlet pipe is connected to a transportation pipe, the other end of the sliding table is providedwith two pushing rods, one pushing rod is provided with a controller, the other end of the transportation pipe is connected to the upper end of a material storage chamber, a filtration layer and an exhaust fan are sequentially arranged in the transportation pipe from left to right, one end of the material storage chamber is connected to a burning chamber, one side inside the material storage chamber is provided with a pushing plate, and one end of the pushing plate is connected to a screw rod. According to the present invention, by improving the burning chamber, the ash collection chamber andthe ash outlet pipe, the cut forage is changed into the plant ash fertilizer through burning, and the obtained fertilizer is the greening grass so as to save the resources; by improving the exhaust fan, the scattered forage can be sucked; and through the conduction pipe and the water box, the flue dust is absorbed, and the advantages of resource saving and environment protection are achieved.