We report here on the fabrication and characterization of nanogapped electrodes for DNA sensing. The gap created with 1,10-decanedithiol is estimated to be ca. 1.3 nm when dithiol-linked nanoparticles were deposited over the gap of the microelectrode as a film. Taking this approach, we can fabricate a molecular electronic device with an electrode spacing accuracy of a few nanometers. Use of the nanogapped electrode has led us to detect very small electrical signals, and therefore it was attempted for DNA sensor applications. The sensing property was intimately involved in measuring the amount of nanoparticle building blocks of the nanogapped array on the microelectrode gap. From the viewpoint of sensitivity, we have conducted a study on the most relevant conditions of film preparation. (C) 2008 The Electrochemical Society.