Properties of polymer materials originate from the large degree of freedom of a single polymer chain. The direct observation of the conformation of single polymer chains would provide much information for the fundamental understanding of the properties of polymers. Fluorescence imaging techniques are suitable for the selective observation of individual molecules embedded in a bulk medium; however, the spatial resolution of conventional optical microscopy is limited to ∼200 nm by the diffraction limit. This paper reviews the state-of-the-art optical imaging techniques that enable to obtain a fluorescence image with a nanometoric spatial resolution and describes its application for the direct imaging of the conformation of individual polymer chains. The conformation of poly(alkyl methacrylate) chains in thin films and micro-phase separation structures of a block copolymer is discussed.