To provide a material transfer device capable of not only transferring a great quantity of material per unit area and per unit time without damaging the same but also energetically discharging, from the outlet, the material transferred to an outlet.

A rotary member 30 rotates with having a center axis on a straight line 36 (imaginary line) passing on a center point of a round top surface 32 and a center line of a round bottom surface 34. A spiral blade 50 is formed on an outer circumference surface 31 of the rotary member 30 and the blade 50 rotates together with the rotary member 30. The blade 50 extends in a spiral shape from a leading end to a trailing end (from end to end) of the outer circumference surface 31 of the rotary member 30. The blades 50 expands from the outer circumference surface 31 of the rotary member 31 to a position close to an inner circumference surface of the casing 20, and material hardly leaks from a gap between a tip of the blade 50 and the inner circumference surface 24. The distance d between mutually facing surfaces of the blade 50 is constant.