PURPOSE: To obtain a cutting device, which allows stable cutting to material to be worked, which is transferred to and fro.

CONSTITUTION: Two cutting knives 12a and 12b are arranged so as to face cutting edges C and C opposite to each other. The cutting knives 12a and 12b are equipped so as to be fixed to cutting knife holders 8a and 8b with fixing bolts 13a and 13b. At respective ends of plane irons 13 and 13 of both the cutting knives 12a and 12b, thin elastic parts G and G are formed so as to make the cutting edges C and C deformable. When pressing force for feeding material is applied, the cutting edge on non-cutting side retreats downwards while the cutting edge on cutting side is held under the condition being brought into contact under pressure with the cutting knife holder 8a or 8b. Due to the above- mentioned difference in levels of both the cutting edges, cutting is performed stably.