PURPOSE: To provide a gasket cutter capable of efficiently producing ring-shaped gaskets high in dimensional accuracy out of sheet-shaped gasket material.

CONSTITUTION: This cutter consists of a rod-shaped member 1 to rotate along the gasket material surface, a pin 21 which is installed roughly orthogonal to the member 1 and pierced through the gasket material to serve as the center of rotation of the member 1, and cutting edges 5 and 8 which are installed on the member 1 so as to be in parallel with the pin 21 and capable of moving for the formation of the inner and outer circumference of the gasket, respectively.