Soil water vapor adsorption and condensation constitute critical non-precipitation water sources in arid and semi-arid ecosystems. However, current research has failed to explicitly differentiate between these two processes, which lead to a substantial overestimation of condensation water quantity. To elucidate the effects mechanistic of varying groundwater depths and vadose zone lithologies on vapor adsorption and condensate formation, nine soil columns with varying lithologies and groundwater levels were established in the arid Yinchuan region of Ningxia. Through layered microlysimeter weighing and temperature-humidity monitoring at different soil depths, the spatiotemporal dynamics of vapor adsorption and condensate formation were quantitatively analyzed. The experimental results demonstrate that (1) shallow groundwater serves as a significant vapor source for condensate formation, with its contribution diminishing progressively as groundwater depth increases. (2) Water vapor adsorption predominantly occurs in the 0-5 cm soil layer (approximately 0.1 mm d- 1) during 19:00-01:00, whereas adsorption in the 5-10 cm layer primarily occurs during 10:00-13:00. (3) With increasing groundwater depth, the dominant vapor source for condensate formation transitions from soil pore vapor to atmospheric vapor.When groundwater depth reaches 2.5 m, its vapor contribution to condensate formation in fine sand and silt soils approaches critical thresholds. (4) Under identical groundwater depth conditions, finer-textured soils exhibit greater condensate quantities and prolonged condensation durations. (5) Conventional microlysimeter methodology may overestimate condensate quantities in arid regions. During soil mass increment processes in the 0-5 cm layer, water vapor adsorption contributes approximately 40% on average, with this proportion further increasing under greater groundwater depths. This study establishes a quantitative foundation for precise estimation of condensate water in arid and semi-arid regions, while deepening the mechanistic understanding of ecohydrological processes associated with condensate formation.