The great scallop Pecten maximus is currently the most important species in landings (as well in tons as in value) for the French inshore fleet of the English Channel. A modelling approach has been proposed in order to better understand the determinism of the distribution of the great scallop, integrating both physical and trophic constraints. Thus a 3D bio]hydrodynamical model (ECOMARS3D developed at Ifremer) providing environmental conditions has been coupled to a population dynamics model and an individual physiological model of scallop. Both these approaches contribute to the understanding of the biogeographical distribution and especially enlighten the respective role of biological or physical factors in defining P. maximus habitat in the English Channel