A new iron phosphate, rubidium zinc iron(III) phosphate, RbZnFe(PO4)2, has been synthesized as single crystals by the flux method. This compound is isostructural to the previously reported KCoAl(PO4)2 [Chen et al. (1997). Acta Cryst. C53,1754–1756]. Its structure consists of a three-dimensional framework built up from corner-sharing PO4 and (Zn,Fe)O4 tetrahedra. This mode of linkage forms channels parallel to the [100], [010] and [001] directions in which the Rb+ ions are located.