Аннотация:Single crystals of (I): CaLaAl3O7 and (II): CaLaGa2.34Al0.66O7 were grown from molten oxide mixtures and investigated by single crystal X-ray technique. Both compounds crystallize with tetragonal symmetry, space group D2d3-P42(1)mBAR, (I): a = 7.8075; c = 5.1564 angstrom, (II): a = 7.9130, c = 5.2360 angstrom, Z = 2 and are isostructural with the Melilites. The crystal structure is discussed.