A new open-framework germanate [Ge15O30(OH)(4)]center dot 2(H(2)tren), denoted SU-69, was synthesized under hydrothermal conditions with tris(2-aminoethyl)-amine (tren) as a structure directing agent (SDA). SU-69 crystallizes in a monoclinic space group (C2/c, No. 15) with a = 20.2656(7) angstrom, b = 11.6250(4) angstrom, c = 18.5602(10) angstrom, and beta = 90.528(4)degrees. The framework of SU-69 is built from a novel Ge13O27(OH)(2) (Ge-13) cluster with two additional GeO3(OH) tetrahedra. Two types of chiral 3,6-net building layers are found in the framework, which alternately stack and connect to form a three-dimensional achiral framework with a two-dimensional 10 x 12-ring channel system. The SDA molecules interact with the framework via H-bonds. The thermal stability of as-synthesized SU-69 has also been investigated.