Small angle neutron scattering (SANS) is considered as a nondestructive technique adoptable for the microstructural characterization of polymeric materials. The possibility to substitute hydrogen for deuterium makes SANS an exclusive technique for investigating macromolecular structures in synthetic and biological polymers. The same method allows a visualization of polymer chains, because of a local contrast between small size ordered domains and amorphous matrix around. In this article, some theoretical bases are reported, and industrial applications of SANS in the polymers field are shown. In particular, SANS investigations of either monoethylene glycol-based polyurethanes, or heat cured and laser machined organic resin microturbines as used for airflow sensing are described. Other examples are mentioned, moreover, showing the usefulness of SANS in characterizing polymers and confirming the improvement of this tool to a level of industrial applicability.