The purpose of this paper Is to develop a simplified localization method for indoor navigation with a few system complexity. It is possible to localization more certain precision by a few sensors, and yet that is effective for application to indoor navigation immediately. The distance and the angle from an acoustic marker with a pair of microphones was estimated by measuring the sound-level (SL) and SL difference, respectively. Through the experiment, it was concerned that proposed method would perform enough to localize the marker, if it was near to the microphones.