A porous medium exploitation method having application to petroleum exploitation is disclosed using coupling between a reservoir model and a near-wellbore model for modelling fluid flows. Fluid flows within the medium are simulated using a reservoir simulator and a near-wellbore simulator. At each time step, the boundary conditions used by the second simulator are calculated by means of with the reservoir simulator. Numerical productivity indices used by the reservoir simulator are calculated by means of using the near-wellbore simulator. The fluid flows within the porous medium during a given period of time are modelled by repeating the previous stages for several time steps. An optimum medium exploitation scenario is deduced determined from this modelling by taking into accounting for, for example, a well damage due to a drilling fluid, an injection of a polymer solution or of an acid solution in the well.