Abstract: A vacuum cleaner cyclone separator having a cyclone with a first end wall, a second opposite end wall (35,36,135), and an intermediate part (38,130), which has the shape of either a cylinder or, at least partly, an up-side-down truncated cone. The intermediate part has an outlet opening (39,131) for particles through which particles separated by the cyclone leave from the intermediate part toward the second end wall. The cyclone is, close to the first end wall, provided with a generally tangentially-directed air inlet (33,129) for dust laden air and also has a tube shaped air outlet (50,142) extending from the first end wall (35) toward the intermediate part and communicating with a vacuum source (15,111).