Abstract: The geological background of perlite deposits worldwide in aspects from ore geological characteristics, metallogenic epoch, rock geochemical model, tectonic background, volcanic eruption model and magma sources, water forms and sources, hydration alteration, perlite deposit genesis and so on was reviewed. The result showed that some problems such as ore forming process and physical and chemical comditions in perlite were still not reasonably interpreted, which restricts studies of the metallogenic theory and prospecting practice of perlite. Finally, some suggestions are given to help the future studies of perlite.