Status Report on the double-\beta decay experiment NEMO-3

The NEMO collaboration is presently mounting the NEMO-3 detector in the Fr\'ejus Underground Laboratory. This detector, which will be completed by the end of the year 2000, is devoted to the search of neutrinoless double beta decay with various isotopes. Much attention has been focused on ^{100}Mo and ^{82}Se with their large Q_{\beta\beta}-values. The detector is based on the direct detection of the two electrons by a tracking device and on the measurement of their energies by a calorimeter. The aim of the experiment is to have a sensitivity for the effective neutrino mass on the order of 0.1 eV. The status and the expected performance of the NEMO-3 detector for both internal and external background rejections and for signal detection are presented.