Two perovskite-type fluorides K2NaVF6 and （NH4）3VF6 were synthesized under mild hydrothermal con- ditions. The structures of the compounds were determined by means of powder X-ray diffraction analysis. The Riet- veld refinement indicates that K2NaVF6 has a cubic elpasolite-type structure and crystallizes in space group Fm3m with lattice constant a=8.3180（2） nm. （NH4）3VF6 has a cubic cryolite-type structure and crystallizes in space group Fm3m with lattice parameter a=9.090（1） rim. The compounds were further characterized by scanning electron micro- scopy（SEM）, thermogravimetric（TG） and differential thermal analysis（DTA）. The variable temperature magnetic susceptibility of these two compounds was characterized for the first time and the result shows that the magnetic or- dering is related to the crystallographic features and isolated magnetic unit with the temperature decreasing.
