  Large Observatory For X-ray Timing (LOFT) is a next generation X-ray
telescope selected by European Space Agency as one of the space mission
concepts within the ``Cosmic Vision'' programme. The Large Area Detector on
board of LOFT will be a collimator-type telescope with an unprecedentedly large
collecting area of about 10 square meters in the energy band between 2 and 100
keV. We demonstrate that LOFT will be a powerful dark matter detector, suitable
for the search of the X-ray line emission expected from decays of light dark
matter particles in galactic halos. We show that LOFT will have sensitivity for
dark matter line search more than an order of magnitude higher than that of all
existing X-ray telescopes. In this way, LOFT will be able to provide a new
insight into the fundamental problem of the nature of dark matter.
