Infiltration is the key process in the rainfall-runoff relationship. Little is known, however, about the seasonal and spatial variability, which is important for the behaviour of the slope surface geomorphological processes.The infiltration rates for contrasting slopes in southeast Spain have been measured by means of simulated rainfall and ponding. A north- and a south-facing slope were selected to analyze effects of aspect. The results show that aspect as well as slope position and vegetation cover determine the steady state infiltration rates.Moreover, seasonal changes play an important role in the soil hydrology. During summer the infiltration rates are high, no runoff is observed on vegetation covered soils. On the bare surfaces, runoff was only 10% of the rainfall. During the wet season, especially in autumn, the infiltration rates are lower, and runoff coefficients equal to 0.3. For the vegetated surfaces, runoff is negligible.Infiltration measurements by means of ponding and simulated rainfall are both suitable to study the infiltration process. In the present study, the infiltration rates measured by cylinder infiltrometer were 8 times greater than by rainfall simulation at 55 mm h−1.