Progress in analytical instruments has stimulated the development of high-performance elastomers, the synthesis of new speciality elastomers, and the elucidation of mechanisms for property enhancements. The use of modern instruments and a combination of ordinary methods of structural analysis have satisfied needs to some extent. However, a newer method of structural characterization is always desired in order to achieve higher orders of information. It is appropriate to review the recent advances in structural characterization of elastomers, especially the characterization of microstructure of polymer chains, from the viewpoints of methodology and applicability of new methods. As to the NMR analysis of elastomers, reviews are available. Here, considerable attention is focused on the procedures for the assignment of signals, because the applicability of a NMR method is based on the reliability of the signal assignments. The other topics are selected to provide direct information for polymer synthesis or polymer properties.