In this paper, we present a novel microfluidic optical sensing system by combining a low-power conductive polymer -based microfluidic pump and a microfluidic chip integrated with an optical sensor. A self priming microfluidic pump is developed using a polypyrrole. A microfluidic chip-optical detector module that contained an optical cuvette with LED and photo-diode optical sensing module was fabricated. Integration of the micro pump and the microfluidic chips complete the sensing system. The pump performance and its application in chemical analysis have been demonstrated in the detection of Fe ions. © 2008 IEEE.