To provide a cutting device for a metal thin plate drum, cutting a metal ring from a cylindrical drum with high accuracy and smoothly delivering the metal ring keeping the accuracy.

A freely rotating drum holding means 3 is inserted in a cylindrical metal thin plate drum D to hold the drum D with the axis turned in the vertical direction. This cutting device is provided with a rotating means 16 for rotating the drum D of the drum holding means 3 round the axis. The device is provided with a drum depress means 20 for clamping the upper edge of the drum D held on the drum holding means 3 and intermittently depressing the drum D at intervals of a predetermined size. The lower end of the drum holding means 3 is provided with an abutting member 17 abutted on the inner surface of the drum D. The abutting member 17 is provided with a cutting means 4 for cutting the drum D in round slices. A table 38 of a delivery means 5 for receiving the metal ring R cut away from the lower end part of the drum D and delivering the same is provided below the drum holding means 3 in the axial direction.