Plant-soil interactions are increasingly recognized to play a major role for terrestrial ecosystems functioning. However, few studies to date have focused on long-term dynamic ecosystems such as forests. Indeed, forest ecosystems are vertically stratified by multiple vegetation strata and the canopy cover manipulation through contrasted stand density management strategies could alter the overall architecture of forest plant community. Very little is known about the cascading effect on soil biodiversity and ecosystem function such as litter decomposition. The aim of this study was to assess the response of a major group of soil fauna, namely collembola, to oak stand density experimental manipulation. A total of 33 stands distributed over a large geographic area were studied covering a wide gradient of stand density, i.e. stand basal area from 2.5 to 43.7 m2.ha-1, stand age, i.e. 18 to 171-year-old, and pedoclimatic context conditions. Our results shown that the response of collembolan assemblages to stand density was highly dependent on stand age. Indeed, collembolan abundance and diversity tend to decrease with stand density reduction in young stands while no response was observed in old stands. Further, a substantial shift of collembolan species composition was observed within young stands and this was strongly associated with contrasted responses among functional groups. Hemiedaphic and euedaphic species abundance and diversity were strongly depleted by stand density reduction whereas epedaphic abundance was unaffected. In contrast, epedaphic diversity tended to be enhanced by stand density reduction. Patterns of collembolan assemblages response to stand density was consistent among pedoclimatic contexts, i.e. mull vs moder. Exploratory analysis using causal diagrams, i.e. path analyses, highlights that those changes were mainly related to understorey vegetation, microclimatic and soil pH condition alterations. These changes of collembolan assemblages could have important functional implications, especially on microbial respiration process through their grazing activities.