In previous our papers, we introduced a preliminary study on the possibility of the development of a new piezoelectric sensor based on boron nitride nanotube(BNNT) which are structurally similar to carbon nanotube(CNT). Unlike CNT, BNNT is an Eco-friendly nanomaterial that has non-cytotoxic property and a promising piezoelectric nanomaterial that can replace conventional piezoelectric sensor such as PZT and PVDF. Smart nanocomposites of CNT and BNNT has a different sensing mechanism that is a piezoresistivity and piezoelectricity. Piezoresistivity is a change of contact resistance in composites of CNT and
piezoelectricity is a change of polarity in composites of BNNT by external force and deformation of the composites. In this paper, we introduced and compared a signal processing mechanism of CNT ,BNNT composites sensor and examined experimental mesurement of the piezoelectric coefficient of BNNT composites by utilize a fundamental data of the BNNT piezoelectric sensor to improve piezoelectric coefficient and we suggested improvement methods of piezoelectric coefficient of the composites.