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Gd3+-doped lead molybdato-tungstates with the chemical formula of Pb1-3xxGd2x(MoO4)1-3x(WO4)3x (wherex = 0.0455, 0.0839, 0.1430, corresponding to 9.53, 18.32, 33.37 mol％ of Gd3+, respectively, as well as denotes cationic vacancies) were successfully synthesized via combustion route. The XRD and SEM results confirmed the formation of single-phase, tetragonal scheelite-type materials (space groupI41/a) with the uniform, spherical and oval grains ranging from 5 to 20μm. Individual grains are strongly agglomerated into big clusters with the size even above 50μm. The magnetic measurements as well as the Brillouin fitting procedure showed paramagnetic state with characteristic superparamagnetic-like behaviour and the short-range ferromagnetic interactions. The electrical and broadband dielectric spectroscopy studies revealed insulating properties with the residual electricaln-type conduction of 2×10-9 S/m and low energy loss (tanδ≈ 0.01) below 300 K. Dielectric analysis showed that no dipole relaxation processes in the Gd3+-doped materials were observed. A fit of dielectric loss spectra of Gd3+-doped samples by sum of the conductivity and the Havriliak-Negami, Cole-Cole, and Cole-Davidson functions confirmed this effect.