The applicability of LLD in neutron dosimetry was tested and the optimum materials were determined. Investigations have been performed on lyoluminescence variations in sensitivity (X-rays and neutrons) for five different materials: the polyalcohols, mannitol and xylitol, the saccharides, trehalose and glucose and the amino acid, leucine. The decisive factor for the choice of a dosimetric material is its tissue equivalence. The results show striking differences in neutron and gamma sensitivities between the dosimetric materials. The different sensitivities for fast neutrons and gamma-rays can be used for simultaneous determination of neutron and gamma doses in mixed neutron photon radiation fields. The successful application of this dosimetric method can be shown by phantom- and in-vivo-measurements.