The invention discloses a spraying device and a spraying switching method thereof. The spraying device includes a switching valve, a spraying loop, a spraying unit, a backflow loop and a backflow slot, wherein the switching valve includes a switching mechanism, an accommodation space, a spryaing outlet and a backflow outlet; the spryaing outlet and the backflow outlet are communicated with the accommodation space; the switching mechanism is rotatably arranged in the accommodation space, and is provided with a covering area and a discharge area; and when the switching valve is switched, the covering degree that covering area coveres one of the spraying outlet and the backflow outlet is equal to the opening degree that the discharge area is corresponding to one of the spraying outlet and the backflow outlet. The spraying device can provide continuous feeding and stable pressure, and can realize uniform spraying and improve the product yield.