PbI2 clusters confined in spaces of LTA zeolite are successfully prepared through vapour phase. An HREM image showed that the crystallinity of the zeolite was preserved after preparation and showed directly that the clusters were incorporated into the α-cages. Absorption spectra were measured by diffuse reflection method as a function of loading density of PbI2 molecules. Several absorption bands from different cluster sizes were observed and showed remarkable blue shift. At the maximum loading, extra reflections, which are forbidden for Fm3A of LTA, were observed in electron and X-ray diffraction patterns. The appearence of the extra reflections and the dependence of absorption curve on the loading density suggest that superlattice of clusters was produced. The characteristic feature of zeolites as containers to make an artificial superlattice of clusters is pointed out.