The structure of sodium aluminophosphate glasses has been studied as a function of composition by Raman speetroscopy. It is found that in glasses with Na2O/P2O5<1 and content up to 10 mol % A13O3, nearly all the alumina is six coordinated, the glass network is mainly built up of (PO3)nn- chains and rings; while in glasses with Na2O/ P2O5≥1 and 5≤A12O3≤20 mol%, A1o4 tetrahedra and different kinds of phosphate groups are formed; but when the Al2O3 conten exceeds 25 mol % and the ratio of Al2O3/P2o5≥0.63, the glass network is mainly built up of AlPO4 groups.