In this paper, the authors propose a MOS-BJT-NDR circuit, which can show the Negative-Differential-Resistance (NDR) characteristic in its current-voltage curve. This NDR circuit is composed of standard Si-based Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) and Bipolar Junction Transistor (BJT). Therefore, they can implement the applications using the standard CMOS process. They demonstrate the design of some logic circuits using the series-connected CMOS-NDR circuit based on the MOnostable-BIstable transition Logic Element (MOBILE) theory. This logic circuit is designed based on the standard 0.18 um CMOS process.