The structure of Sr3ZnIrO6was determined by powder X-ray Rietveld refinement in space group R 3c(No. 167),a= 9.6392(1) andc= 11.2145(2) Å. Neutron diffraction refinements confirm the structure analysis. The structure contains zinc in a highly unusual trigonal prismatic coordination environment. The structure consists of infinite one-dimensional chains of alternating face-shared IrO6octahedra and ZnO6trigonal prisms. Magnetic measurements show that Sr3ZnIrO6correlates antiferromagnetically near 20 K. No magnetic ordering, however, was found by the neutron diffraction experiments performed at room temperature and at 10K. The magnetic data were fit using an Ising model, which gave a coupling valueJ/kB∼ 18.5.