Abstract: A new laser transverse mode demonstration system based on the loss adjustment of a cat-eye reflector is presented in this paper. A cat-eye corner reflector made up of a convex lens and a concave mirror adjustable in five degrees of freedom was used to form a lasing chamber capable of adjusting the loss. The change of the state of the laser transverse mode was realized by changing the loss factor of the lasing chamber through adjusting the cat-eye corner reflector. When one or some position parameters of the convex lens or the concave mirror were changed, the power loss and the symmetry of the laser resonator produced the relative changes of diffraction losses. Over twenty clear highorder transverse mode images were collected by CCD and stored in computer.