Five different kinds of crystalline structures in the Li2O-WO3 binary system were selected and an ensemble of eight cluster models containing Na+ cation was built in this paper. DFT (density functional theory) calculation of their Raman-active vibration wavenumbers together with scattering activities were performed based on MS (Materials Studio) CASTEP (Cambrigde Serial Total Energy Package) Program and Gaussian09 code, respectively. The wavenumber of W-Onb (non-bridging oxygen) Raman symmetric stretching vibration mode were found to increase with the decrease of W-Onb bond length not only for crystals but also for melts. In order to reflect the influence of local stress on the wavenumber of W-Onb symmetric stretching vibration mode, the micro-structures in crystals and melts were identified, respectively. Results show that bulk crystals usually contain [WO6]6- coordinated groups in the Li2O-WO3 binary system, the wavenumber of W-Onb symmetric stretching vibration mode in [WO6]6- will increase with the increase of the number of bridging oxygen; while in the melt, the wavenumber of W-Onb symmetric stretching vibration mode generally follows: [WO4]2- > [WO5]4- > [WO6]6-. When the W-O group is determined, this wavenumber will increase with the increase of the number of bridging oxygen. The correlation is helpful for the diagnosis and identification of the anion groups in the crystalline and molten alkali tungstate compounds. The in-situ Raman spectra of molten A2WnO3n+1 (A = Li, Na, K; n = 1, 2, 3) have been measured in order to verify the correlation obtained in this paper.