The implementation of the Water Framework Directive implies the intensification of the monitoring of contaminants such as pesticides. For this purpose different strategies can be developed: grab or automated sampling (fractioned, weekly averaged) and passive sampling. In the present study, Stir Bar Sorptive Extraction (SBSE), a solvent free sample preparation technique, has been coupled to liquid desorption and LCMSMS quantification for the extraction of sixteen selected pesticides. For in-situ application, the same PDMS coated bars from Gerstel were directly placed in the river as passive samplers. The mass of each pesticide adsorbed during one week was compared to the mass resulting from the extraction of weekly averaged automated sampling with SBSE. Two different series of assays were conducted, to evaluate the repeatability of the experiments and the sorption kinetics (with different exposition lengths). Results from SBSE exposed one week on-site and extraction of water collected with automated sampler during the same period proved that SBSE used as passive sampler could be usefull to detect and quantify pesticides in river waters. Considering kinetic aspects, we noticed that the results obtained during two weeks of expositon could be compared to the sum of the two independent weeks. Adsorption on SBSE should then be linear during the studied period for most of the compounds. This study represented a first in-situ application of SBSE for pesticide quantification. We demonstrated the relevance of such a technique which required not much organic solvents compared to other tools (POCIS, SPMD). Nevertheless, in order to be really used as passive samplers laboratoratory calibrations are needed, as it is done for the other passive samplers.