In Mediterranean region, summer droughts are getting more intense with climate change, and water management is essential to avoid grapevine water and nitrogen (N) stress in order to maintain berry production (Celette and Gary 2013). Numerous studies have shown the potential of service crops for providing services in vineyards, eventually in relation to water and N supply (Garcia et al. 2018). Functional characterization is increasingly employed for cultivated ecosystems (Martin and Isaac 2015; Wood et al. 2015), with the hypothesis that functional markers could help us to predict the ecosystem services provided by cash crops and service crops (Damour et al. 2015). However, there is a lack of studies that assess the relations between functional markers and ecosystem services in field conditions. The aim of this study was to test the relations between functional markers of service crops in vineyards, and water and N stocks in soils. The experiment was carried out from 2016 to 2017 on a vineyard located in the South of France. Treatments consisted in 13 different service crop species and spontaneous vegetation in the inter-rows. Species were chosen to diversify botanical families, life cycles and growing behaviour. Service crops were sown on plots of 30m length in inter-rows. We studied plant communities of sown species and neighbouring weeds in three quadrats per treatment. At budburst, cover rate and aboveground biomass were recorded in all quadrats, and species were sort out to calculate their relative abundance. After biomass collection, soil cores were collected to measure soil water and N contents. Aboveground functional markers were measured on sown species and most frequent weeds (39 species in total) according to standardized protocols (Pérez-Harguindeguy et al. 2013). We recorded plant height, leaf area, leaf dry matter content, plant dry matter content, specific leaf area (SLA), carbon, N content and C/N ratio. Community weighted means (Garnier et al. 2004)