The invention relates to fusion proteins including at least a swollenin and at least a plant cell-wall degrading enzyme, the swollenin, and plant cell-wall degrading enzyme, being recombinant proteins corresponding to native proteins in fungi, or mutated forms thereof. The invention also relates to the use of fusion proteins as defined above, for carrying out processes of plant cell-wall degradation in the frame of the preparation, from plants or vegetal by-products, of compounds of interest located in plant cell-wall, or in the frame of the bleaching of pulp and paper, or for biofuel production, or food industries.