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Water content and movement in soil profile and hydrogen isotope composition (dD) of soil water, rainwater, and groundwater were examined in a subalpine dark coniferous forest in the Wolong National Nature Reserve in Sichuan, China, following rainfall events in 20032004. Light rainfall increased water content in the litter and at soil depth of 080?cm, but the increased soil water was lost in several days. Heavy rainfall increased soil water content up to 85% at depths of 040?cm. Following the light rainfall in early spring, the dD of water from the litter, humus, illuvial, and material layers decreased first and then gradually reached the pre-rainfall level. In summer, light rainfall reached the litter humus, and illuvial layer, but did not hit the material layer. Heavy rainfall affected dD of water in all layers. The dD of soil interflow slightly fluctuated with rainfall events. The dD of shallow groundwater did not differ significantly among all rainfall events. Light rainfall altered the shape of dD profile curve of water in the upper layer of soil, whereas heavy rainfall greatly affected the shape of dD profile curve of water in all soil layers. Following the heavy rainfall, preferential flow initially occurred through macropores, decayed plant roots, and rocks at different depths of soil profile. With continuing rainfall, the litter and surface soil were nearly saturated or fully saturated, and infiltration became homogeneous and plug-like. Forest soil water, particularly in deeper soil profile, was slightly affected by rainfall and, thus, can be a source of water supply for regional needs, particularly during dry seasons. Copyright (c) 2011 John Wiley & Sons, Ltd.