Three types of ternary selenides with layered composite crystal structures (PbSe)1.14NbSe2[A], (PbSe)1.14(NbSe2)2[B] and (PbSe) 1.14 (NbSe2)3[C] have been prepared as powder samples. All the samples were characterized by both electron diffraction and X-my diffraction. A dependence of the products on the preparation temperature and composition has been examined. It has been found that intercalation occurs for the selenides [B] and [C] through the treatment with hydrazine monohydrate. The atomic coordinates in the layer-stacking direction of [B], [C] and their intercalation compounds have been determined on the basis of a Rietveld analysis of the X-ray diffraction profile of 00l diffraction lines.