The utility model provides a liquid pressure -shear driving machine for $favoring cut in area, includes the pneumatic cylinder that the level was placed, and the jar seat and the cylinder end of pneumatic cylinder are articulated with hank axle bed and crank piece respectively, and crank piece not hinged end is installed in the axis of rotation, and the axis of rotation both sides are passed through the wheel and rack guide pillar and are linked to each other, and it is continuous with the last blade holder of upper end that the rack guide pillar passes the lower tool post, be provided with cutting blade between the upper and lower blade holder, the rack guide pillar is provided with uide bushing, uide bushing and rack guide pillar sliding fit with lower tool post contact segment, the crank piece arm of force is greater than the reference radius of gear. When cuted in thick area, the release of pneumatic cylinder cylinder end drove the crank piece and rotates, and the gear and the axisof rotation of both sides are rotated thereupon, drove and followed the uide bushing downstream with both sides gear engagement's two rooted tooth strip guide pillars, and the upper slitter of beingconnected with the rack guide pillar is located in down, realizes cuting, the utility model has the characteristics of the atress is even, reduction in production cost.