A powder recycling system includes a supply tank, a continuous loss-in-weight module, a pneumatic module, a transfer channel, a recycle module, and a refilling tank. The supply tank accommodates recycling powder. The continuous loss-in-weight module includes a storage tank receiving the recycling powder from the supply tank and a rotary output pipe connected to the storage tank to output the recycling powder. The continuous loss-in-weight module controls the mass flow rate of the output of the recycling powder according to the weight change of the storage tank. The pneumatic module enables the recycling powder to float and move in the transfer channel. The recycle module is connected to the transfer channel to receive the recycling powder, sieves the recycling powder, provides virgin powder, and mixes the virgin powder with the recycling powder. The refilling tank is connected to the recycle module to receive the recycling powder and the virgin powder.