The crystal structure of dibarium triferrite Ba 2Fe 6O 11 has been solved by direct methods, using intensity data collected by means of an automated diffractometer (MoKα radiation) and corrected for absorption. It crystallizes in the orthorhombic space group Pnnm: a = 23.024(10)Å, b = 5.181(3) Å, c = 8.900(4) Å, Z = 4. Program MULTAN was successfully used for locating Ba 2+ and most of the Fe 3+ ions. The structure was further refined by conventional Fourier and least-squares methods (full-matrix program) to a final R value of 0.045 for 1448 observed reflections. Fe 3+ ions occur in both octahedral (FeO mean distance: 2.02 Å) and tetrahedral (FeO mean distance: 1.865 Å) coordination. Two types of Ba 2+ ions are found, with six and seven neighboring oxygen atoms. The structure consists of sheets of edge-shared FeO 6 octahedra which are connected by means of corner-shared tetrahedra.