The invention relates to a device (1) for cutting human or animal tissue, such as a cornea (3), or a crystalline lens, said device comprising a femtosecond laser (2) that can emit a L.A.S.E.R. beam (4) in the form of impulses, and means for directing and focusing said beam onto or into the tissue for the cutting thereof as such. According to the invention, the device comprises means (9) for shaping the L.A.S.E.R. beam (4), which are positioned in the trajectory of said beam, and can modulate the energy distribution of the L.A.S.E.R. beam (4) in the focal plane thereof, corresponding to the cutting plane.