A powder feeding device includes: a hopper including a discharge port for discharging powder; and a conveyance device configured to move a conveyance surface disposed below the discharge port in a first direction and invert the conveyance surface in a front end portion. The hopper includes a front wall portion positioned on a downstream side of the discharge port in the first direction. A predetermined gap is formed between a lower end of the front wall portion and the conveyance surface. In the powder feeding device, powder deposited on the conveyance surface is conveyed in the first direction by the conveyance device with a thickness corresponding to the gap and dropped from the front end portion.