Late Pleistocene glaciations in the NW Iberian Peninsula over Serra de Queixa and Serra de Xurés, all with granite substrata, were studied by mass spectrometry using cosmogenic 21 Ne. Rock cores were drilled in glacial polished surfaces and push moraine boulders, and were analyzed to determine their integral exposure time to cosmic rays. First results, which are consistent with the relative géomorphologie model estimates, allow the identification of at least three different glacial stages, with the latest one terminating about 75 Ka B.P.