Abstract: The ESR spectra of three reduced heteropolyanions belonging to Lindqvist structure are reported in this paper. At room temperature and appropriate pH range the ESR spectrum of VMo₅O₁₉^4- contains 8 hyperfine lines and the spectra of V₂W₄O₁₉^5-and V₃W₃O₁₉^6- contain 15 hyperfines lines. These 15 lines gradually change their shape and finally become a eight-line spectrum after a longer period of time. We have successively simulated these complex 8 + 15 spectral lines by superposition of the 8 line with 15 line spectrum at different ratios. The ESR parameters of 77K frozen spectra are determined and the approximate K, α values are calculated based on LCAO-MO theory. The results are compared with those of Keggin structure polyanions. It is found that the K, α values of Keggin structure are smaller due to the extra delocalization originated from the additional corner-shared oxygen presented in the Keggin strcture.