The beta-modification of Li3AlF6 has been prepared by heating an appropriate mixture of LiF and AlF3 at 820 degrees C under argon atmosphere and subsequently slow cooling it to room temperature. beta-Li3AlF6 is isotypic to beta-Li3VF6 and crystallizes in C2/c with a = 14.201(1) Angstrom, b = 8.387(1) Angstrom, c = 9.860(1) Angstrom, and beta = 94.07(1)degrees. The structural parameters have been refined by Rietveld analysis from powder data. A comparison of the structures of beta-Li3AlF6 and beta-Li3TiF6 is made for the analysis of a static Jahn-Teller effect within quasi-isolated [TiF6](3-) octahedra. Calculations of the Madelung part of the lattice energy were performed to discuss the chemical bonding.