Potentiometric electrolytic sensor is currently a widely used technique for detecting poisonous sites. In this respect, foreign technology is leading, so most of these sensors rely on imports. Potentiometric electrolytic gas sensor structure: in a cylindrical plastic cell body, the installation of the working electrode, the electrode and the reference electrode, between the electrodes filled with electrolyte, made of porous tetrafluoroethylene diaphragm, in the Top package. Preamplifier and sensor electrode connection between the electrodes in the application of a certain potential, the sensor is in working condition. Gas and electrolyte within the working electrode oxidation or reduction reaction occurred in the reduction or oxidation of the electrode reaction, the equilibrium potential of the electrode changes, the value of change is proportional to the gas concentration.