<正>The nano-titanium dioxide (nano-TiO2) sensing membrane,fabricated by sol-gel technology,was used as the pH-sensing layer of the extended gate field effect transistor (EGFET) device.The objective of this research is the preparation of titanium dioxide materials by sol-gel method using Ti(OBu)4 as the precursor.In this study,we fabricated a nano-titanium dioxide sensing layer on the ITO glass by dip coating.In order to examine the sensitivity of the nano-TiO2 films applied to the EGFET devices,we adopted the ITO glass as substrate,and measured theⅠDS-ⅤG curves of the nano-titanium dioxide separative structure EGFET device in the pH buffer solutions that have different pH values by the Keithley 236 Instrument.By the experimental results,we can obtain the pH sensitivities of the EGFET with nano-TiO2 sensing membrane prepared by sol-gel method,which is 59.86mV/pH from pH 1 to pH 9.