For future medical and lifescience applications, we have developed nanophotonics-based novel bio-analytical devices. Living organisms maintain their functions by biomolecular interactions such as DNA hybridization and antigen-antibody reactions. To understand their functions, bioanalytical methods, such as enzyme-linked immunosorbent assay (ELISA), polymerase chain reaction (PCR), and gel electrophoresis, have been widely used. However, these methods has several disadvantages, such as low sensitivity, sophisticated liquid handling, long assay time, and labeling procedures. To overcome these disadvantages, highly sensitive, more simplified, and label-free baioanalytical devices had been desired. To develop nanophotonics-based bio-analytical devices, we have focused on specific optical characteristics from nanostructures, such as localized surface plasmon resonance (LSPR), quantum dots (QDs) and photonic crystals (PhC). Using these optical characteristics, the refractive-index change due to biomolecular interactions, such as DNA hybridization and antigen-antibody reactions, can be detected without any labeling procedure using fluorescent dyes and enzymes. In this paper, we present our nanophotonics-based bioanalytical devices using LSPR and PhC. Based on these nanophotonics-based bio-analytical devices, in the future bioanalysis can be drastically simplified.