With the recent development of an X-ray source, focusing optics, and X-ray detectors, microbeam Xray scattering techniques have been well established and widely applied to the characterization of polymeric materials. Microbeam X-ray scattering is a unique and powerful tool that provides abundant information on local structures, such as the spatial inhomogeneity of materials and the structural change at a local position. Furthermore, by combining microbeam small-angle X-ray scattering (SAXS) and wide-angle X-ray scattering (WAXS), the observable spatial scale range is from several to several hundred angstrom, which is the most important scale range in the hierarchical structure analyses of polymers. In this review, the representative applications of microbeam X-ray scattering to polymer crystallization, spatial inhomogeneity analyses, stress transfer under external field and the microphase separated structure analyses in block copolymer systems are introduced.