Feeding device of box filling machine

The utility model provides a feeding device of a box filling machine, which comprises a conveying mechanism, a horizontal pressing plate mechanism and a vertical pressing plate mechanism, wherein the conveying mechanism is used for vertically conveying paperboards, and the horizontal pressing plate mechanism and the vertical pressing plate mechanism are used for limiting the paperboards. The horizontal pressing plate mechanism comprises a horizontal pressing plate assembly arranged on one side or two sides of the conveying mechanism in a sliding mode and a first driving piece used for driving the horizontal pressing plate assembly to move in the paperboard conveying direction. The vertical pressing plate mechanism comprises a vertical pressing plate assembly arranged at the tail end of the conveying mechanism and a second driving part used for driving the vertical pressing plate assembly to ascend and descend, a box blocking part is arranged on the vertical pressing plate assembly, and/or a box blocking part