Ba(Mg1/2W1/2)O3 ceramic was synthesized using a conventional solid-state reaction method at 1500 degrees C for 4h. The face-centered cubic crystal structure of the material was confirmed by Rietveld refinement of X-ray diffraction (XRD) data, and vibrational modes were obtained by Raman and Fourier transform far-infrared (FTIR) reflection spectroscopies. First-principle calculations based on density functional theory with local density approximation were used to calculate Gamma-point modes and dielectric properties of Ba(Mg1/2W1/2)O3. The Raman spectrum with nine active modes can be fitted with Lorentzian function, and the modes were assigned as F2g(1) (126cm-1), F2g(2) (441cm-1), Eg(O) (538cm-1), and A1g(O) (812cm-1). Far-infrared spectrum...