PURPOSE: To regulate a clearance between opposed shearing blades in simple structure so as to prevent the clearance from being expanded and shear a material to be cut with a small shearing force.

CONSTITUTION: In a metal material cutting device which is provided with shearing blades 10R and 10L mounted at their respective opposed positions on a pair of arms 2L and 2R and an arm drive mechanism 8 which opens the arms 2L and 2R like scissors, there are formed projected parts 11L and 11R projecting more inwardly from the points of the blades 10L and 10R at the tips of the paired arms 2L and 2R. Binding members 15L and 15R which regulate a clearance between both shearing blades 10L and 10R are mounted to the projected parts 11L and 11R.