A defrosting air port for an excavator driving cab is characterized in that at least two air outlets are formed on an air duct mounted on a front control box; the air outlets respectively face to an upper piece of glass and a lower piece of glass and can respectively conduct defrosting operations to the upper piece of glass and the lower piece of glass; angles of intersection are formed between the axial directions of the air outlets facing to the upper and the lower pieces of glass and the surfaces of the upper and the lower pieces of glass, so as to ensure that certain angles are formed between the air outlets and the upper and the lower pieces of glass, reduce air-flow resistance and enable air flows to smoothly flow around along the surfaces of the upper and the lower pieces of glass; and shutters which swing horizontally or vertically are arranged on the air outlets. The defrosting air port for the excavator driving cab has the advantages as follows: defrosting control can be conducted to the upper and the lower pieces of glass respectively, the defrosting air port can be opened and closed, the air speed can be controlled at discretion, and the air direction can be adjusted at discretion. The air direction and the air speed can be controlled according to the distributing circumstance of frost and water mist on the upper and the lower pieces of glass, the defrosting efficiency is high, and the use is convenient.