Abstract: The structure of Na₂O-B₂O₃-V₂O₅ glasses is studied by the ⁵¹V NMR technique. The results show that,
1) as R<0.5+K, the NaV₃O₈, NaVO₃ and NaVO₃-B units are formed successively with the increasing of R.
2) as R=0.5 + K, all the V₂O₅ units are transformed into NaVO₃ and NaVO₃-B units.
3) as R>0.5 + K, the number of NaVO₃-B units decreases accordingly as the increasing of nonbridge-oxygen atoms in borate units, and it can be guessed that the boron atoms in NaVO₃-B are 4-coordinated.

Key words: Glass, Borate, Vanadate, NMR