Abstract: A device for taking a sample of fluid from a drum includes a dip-tube having at its lower end a closure member, a piston having at the end of a rod a disk adapted to slide in the dip-tube, to which it is sealed, and members for temporarily positioning the piston disk in the heightwise direction. A support ring is adapted to rest on the periphery of the filler orifice of a substantially horizontal wall of the drum and has a passage in which the dip-tube slides and to which the dip-tube is sealed, the disk remains inside the dip-tube at all times, and the closure member is in the form of a fixed end-piece in which is provided an orifice provided with non-return means enabling fluid to be aspirated into the tube but preventing the fluid from escaping under it own weight.