A ladder hoist device for hoisting material up an extension ladder. The ladder hoist device includes a device that is able to move materials up and down an extension ladder. The device has a back plate. The back plate has a front side, a back side, a top edge and a bottom edge. A support plate supports the materials. The support plate has an edge fixedly coupled to the front side of the back plate. A mounting frame has a plurality of rollers for guiding the back plate along the rails of the ladder. A plurality of brackets rotatably couple the rollers to the back plate. Each of the brackets is coupled to each other and to the back plate. The rollers engage the ladder. A pulley system pulls the back plate up the ladder.