Lithium magnesium molybdate (Li 2 Mg 2 (MoO 4 ) 3 ) crystals were grown by the low-thermal-gradient Czochralski method. Luminescence properties of the material (emission spectra, thermally stimulated luminescence, dependence of intensity on temperature, phosphorescence) have been studied under X-Ray excitation in the temperature interval from 8 K to 400 K, while at the same being operated as a scintillating bolometer at 20 mK for the first time. We demonstrated that Li 2 Mg 2 (MoO 4 ) 3 crystals are a potentially promising detector material to search for neutrinoless double beta decay of 100 Mo.