The invention relates to a double battery current-type nitrogen oxide sensor chip and a preparation method thereof. The preparation method comprises carrying out curtain coating and cutting to obtain a curtain-coated substrate corresponding to each layer, wherein the nitrogen oxide sensor chip has a structure composed of the three substrates, carrying out corresponding screen printing on all the curtain-coated substrates to obtain current-type double cells composed of equal active and non-active electrodes and a common counter electrode and to obtain a heating resistor and a corresponding functional layer, overlaying all the curtain-coated substrates to obtain a chip blank, cutting the blank to obtain a single core blank, and sintering the single core blank to obtain the double battery current-type nitrogen oxide sensor, wherein in sintering, the corresponding functional layer forms a cavity after glue discharge and the cavity and a related structure form an air channel. Compared with the existing nitrogen oxide sensor chip, the double battery current-type nitrogen oxide sensor chip has the characteristics of simple preparation processes and low cost. The double battery current-type nitrogen oxide sensor chip has measuring accuracy and can simultaneously detect nitrogen oxide content and oxygen content.