Provided are an apparatus and method for supplying powder quantitatively and a material supply apparatus including the apparatus for supplying powder quantitatively. The apparatus for supplying powder quantitatively to a place where required includes: a driving part generating a driving force using an external power; a powder supply part connected to the driving part, following the operation of the driving part, and transferring the powder according to a predetermined path; a chamber placed on the sides of the powder supply part and receiving the powder transferred by the powder supply part; a compression part compressing the transferred powder in the chamber; and a quantitative supply part separating a desired amount of powder from the compressed powder and discharging the separated powder from the chamber. The method of supplying powder quantitatively to a place where required includes: a preparation operation of receiving powder and preparing for the transfer of the powder; a powder transfer operation of transferring the powder to a chamber having a predetermined volume according to a predetermined path using a powder supply part that is driven by an external power and transfers the powder; a compressing operation of making the compressed bulk of powder by compressing the transferred powder in a compression part of the chamber; a separating operation of separating a desired amount of powder from the powder that is compressed and bridged in the chamber using a separating means; and a discharge operation of discharging the separated powder to the outside.