The surface of the misfit-layer compounds (LaSe)xNbSe2 and (PbSe)xNbSe2 is studied by means of scanning tunneling microscopy (STM) and atomic force microscopy (AFM), in air and nitrogen, in the range of 0.5 to 10 μm2. The cleaved surface of (LaSe)xNbSe2 presents flat non-stepped surfaces which crack and react. Inner layers do not appear to crack. The dynamic process taking place in the superficial layers produces pieces which arrange in a self-similar way and eventually gives rise to discrete islands which self-organize periodically in one direction. On the other hand, the cleaved surface of (PbSe)xNbSe2 is stepped and shows no reactivity. The influence of the cleavage, the strain, the strength of the interlayer and intralayer bonding, and the misfit of the compounds are discussed as reasons for the mesoscopic behaviour of these materials.