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Since the Northeast of Brazil suffers from water scarcity and an excessive use of subfossil to fossil groundwaters, the assessment of seepage (SP) and groundwater recharge (GR) under the present semi-arid climatic conditions is important. Simulated SP-periods (in days) in two out of three investigated soils were identical compared to measured SP-periods showing that the applied soil water balance model HILLFLOW calculated realistically. Under grass vegetation (Haplic Acrisol) and under natural drought deciduous shrub vegetation (Lixi-Ferric Alisol), a distinct higher portion of precipitation is consumed by actual evapotranspiration than under cassava vegetation (Ferralic Arenosol), leading to a SP-portion, which is in both soils only the half compared to the Ferralic Arenosol. The simulated subterranean water divide in the Ferralic Arenosol lies higher (150-175 cm depth) when the vegetation cover is cassava and deeper (350-400 cm depth) when the vegetation cover is drought deciduous shrub. The rate of GR in 5 m depth under the Ferralic Arenosol was calculated at about 15 mm(.)a(-1) under cassava vegetation and 7 mm(.)a(-1) under drought deciduous shrub vegetation (mean: 10.5 mm(.)a(-1)), which is highly comparable to the referenced value of 10 mm(.)a(-1).