Single molecule junctions, in which a single molecule bridges between metal electrodes, have attracted wide attention. It is because novel properties can appear in the single molecule junction due to its peculiar geometrical and electronic characters. The single molecule junction has also attracted attention due to its potential application in ultrasmall electronic devices, where single molecules are utilized as active electronic components. Thus, fabrication of single molecule junctions, as well as understanding and finding their unique properties (e.g. conductance, optical and magnetic properties), have become long-standing goals of scientists and engineers. Along with our studies on single molecular junction, the following subjects are reviewed (i) fabrication of single molecular junction (ii) characterization (iii) finding novel properties appeared in the single molecular junction.