Abstract : An original modeling of landscape erosion is proposed in order to estimate the valley deepening in relation with tectonics, relief and valley width, lithology, climate and sea-level change. It is based on the coupling between a fluvial erosion equation including width of river action (a concept which is infrequently used and which represents the width on which the river acts on the long range, erosion or deposits during the time of a climatic stage or more), and a slope evolution modeling. The evolution of hydraulic and sedimentary parameters (like flow rate, channel width or denudation rate and sedimentary load due to slope erosion) during the Quaternary was built from the results of the European project BIOCLIM for the climatic modeling. Put into practice with Seine and Marne valleys data, this model provides a good assessment of erosion and deposits process (incision amplitude and terrace thickness are estimated with an accuracy of 1 meter) and a better understanding of mechanisms and controls. In the upstream part of the river, the fluvial processes are dominated by climatic changes whereas eustatism, tectonics, climate and submarine topography drive at once the evolution of the valley in the downstream part. Besides, the analysis of test cases computed with several values of tectonic uplift allows us to present a map reporting the uplift rate in these Marne and Seine valleys. Finally, theses simulations of the landscape evolution in the past enable to specify coefficients and calibrate the model in preparation for prospective calculations.