The object of this paper is to describe the process and current status of the development project of an Ultra Precision Gear Measuring Instrument that guarantees a measurement accuracy that falls into a submicron range. The angular indexing mechanism, which is the basis of its measurement accuracy, consists of a purely mechanical system. The system is based on the concept of accuracy feedback where its own deviation estimated from measurement results is fed back into the finishing process. It consists of basic axes with minimum error causing factors in order to seek the optimum accuracy that can be achieved by precision machinery. The measurement accuracy of this measuring instrument has already reached the submicron range in its initial assembly state.