An automatic cat litter box cleansing structure includes a base on where the cat litter box is disposed; a horizontal movement module movably disposed on the base and transversely moving along the area in which the cat litter box is disposed; a vertical movement module movably disposed on the horizontal movement module and longitudinally move with respect to the horizontal movement module. With the control module controlling the horizontal movement module and the vertical movement module to move, the shoveling member automatically shovels the cat feces away from the cat litter box, achieving an automatic cleansing function.