Five organic−inorganic hybrid mixed-metal oxalatophosphates, (C3H12N2)2[(VO)2(ox)Ga2(PO4)4] (1), (C10H28N4)[(VO)2(ox)Ga2(PO4)4]·2H2O (2), (C7H21N3)0.5(H3O)[Mn(H2O)2Ga4F2(ox)(PO4)4]·4H2O (3), (C5H14N2)[Mn(H2O)2Ga4F2(ox)(PO4)4]·3H2O (4), and (C4H16N3)[MnGa2(ox)2(HPO4)2(PO4)] (5) (ox = C2O42-), with varied framework topologies, have been synthesized under mild hydrothermal conditions and characterized by single-crystal X-ray diffraction, magnetic susceptibility, and TG analysis. They provide foremost examples of organic−metallophosphate hybrid frameworks that contain hetero metal centers, owing to which the structures of 1−5 are able to be indexed into a series. The vanadium compounds 1 and 2 are layered, whereas the manganese compounds 3, 4, and 5, compositionally and structurally related to 1 or 2, are 3D materials. The oxalate anion can act as a bis-bidentate ligand in all five compounds as well as a monobidentate ligand in 5. Besides homo bioctahedral units of M‘2(ox)O6 (M‘ = (VO) for 1 and 2, (GaF) for 3 and 4), we observe the first hetero chelating MnGa(ox)O8 unit, formed of an unusual Mn[6p]O6 trigonal prism and a GaO6 octahedron, and unique trimeric polyhedral Mn(H2O)2(GaF)2O12 and MnGa2O16 units. The fundamental frameworks for 1−5 effectively display a series that is constructed from a substructure of 1D or 2D plus a four-ring linker and/or Mn2+ ions into 2D or 3D structures. The hetero metals have imposed magnetic property to the Ga(ox)PO lattices and led to the first well-defined M−X−Ga (X = O, F) bonds ever observed in the metal phosphate chemistry.