A shredder device, in particular for agricultural machines, comprises a bearing structure, able to be stably associated with a drive machine and defining, in cooperation with the ground, a cutting chamber, at least a rotor rotatable around an axis of rotation, assembled on said bearing structure and housed inside said cutting chamber, a plurality of blades, supported on said at least one rotor and extending away from the axis of rotation of said rotor to intercept and shred material deposited on the ground. Each of said blades is rigidly constrained and in a stable position on said rotor. The shredding action is improved thanks to the use of counter-blades, assembled in a fixed position on said bearing structure and each one operatively associated with a respective blade so as to generate a scissor-like shredding action on the material to be shredded.