The invention discloses a digging and fertilizing device for forestry planting, and the digging and fertilizing device for forestry planting comprises a bottom plate, a drill rod, a spiral blade, a first threaded rod, a first sleeve, a connecting rod, a mounting rod, a roller, a door type frame, a mounting plate, a first motor, an annular water pipe, a spray head, a fertilizer water tank, a two-way screw rod, a second motor, a second sleeve, a connecting rod and an adjusting device, wherein the adjusting device comprises a second threaded rod, a first helical gear and a second helical gear. The digging and fertilizing device is provided with the first threaded rod, the connecting rod, the mounting rod and the roller, the whole device is stably supported and fixed, the movement of the device is facilitated, the digging and fertilizing device is provided with the second motor, the two-way screw rod, the connecting rod, the mounting plate and the adjusting device for adjusting the distance between the drill rod and the ground, so that the drilling depth can be adjusted, the fertilizer water tank, the annular pipe and the spray head are arranged for spraying water and fertilizers to dug pits, and the work efficiency is improved.