The urgency to replace fossil fuels with renewable ones, together with the growth of biodiesel production and, consequently, of glycerol in Brazil and in the world, stimulate research in order to transform products derived from biomass into others with greater added values and, therefore, maintain the production chain. . The gas phase dehydration reaction of glycerol to acrolein using acidic solids is an interesting reaction pathway. Catalysts were prepared with different contents of magnesium spinel dispersed in Beta zeolite and their glycerol dehydration performances were evaluated. The different solids were characterized by XRD, XRF, MPE, infrared (FTIR), Raman spectroscopy, nitrogen physisorption, SEM-FEG, acidity by TPD-NH3 and DRIFTS-pyridine adsorption. It was not possible to observe the spinel phase in the diffractograms due to its high dispersion, while the reflections of H-BEA were evident in the different samples. The Raman and infrared spectra suggested the presence of stretches referring to the MgAl2O4 spinel. Nitrogen isotherms and low-angle diffractograms indicated that the pore structure and textural properties were altered after impregnation, but the micro-mesoporosity of the zeolite was maintained. The morphology of H-BEA was not significantly altered by modification with spinel and the metals are highly dispersed according to SEM and EDS spectral mapping. Crystal sizes range from 30 to 160 nm and specific areas range from 721 to 222 m2g−1, depending on the MgAl2O4 content. According to the TPD profiles and the DRIFTS spectra, the addition of spinel to the zeolite caused a change in the acidic properties of H-BEA. The catalyst with 2% MgAl2O4 under H-BEA showed the best catalytic performance reaching 60% glycerol conversion, 66% acrolein selectivity in 6 h and 16% deposited coke in 10 h, restricting deactivation compared to pure zeolite. . The reaction pathways for the different products formed depending on the type of acid site were detailed in the proposed mechanism and correlated with the electrostatic potential maps, as well as the reactions for the formation of coke were described according to the compounds identified by GC-MS after coke extraction.