Suffusion involves a selective erosion of fine particles in a soil by the water seepage in the matrix formed by coarser particles. This phenomenon can induce a change in particle size distribution, porosity and hydraulic conductivity of the material. With the objective to characterize the soil sensibility and propose suffusion sensibility classification, a series of one-dimensional downward seepage flow tests was realized with an erodimeter. Tests were performed under controlled hydraulic gradients in binary mixtures of sandy gravel soils. Two controlling parameters were used: 1) fine content and 2) hydraulic loading history. An analysis based on energy induced by the seepage flow is proposed to characterize the hydraulic loading and the cumulative eroded dry mass to characterize the soil response. The results show that for a given soil different hydraulic loading histories result in different soil sensibilities. Soils with the lowest fine contents tend to require larger flow energy for the development of erosion. These results demonstrate that this approach is effective to characterize suffusion sensibility for cohesionless soils.