Nitrogen oxide (NO) exhaust gas has deteriorated the natural air environment. In this article, the pulse streamer discharge technique is applied to remove such gas. Emission spectra indicate that NO has been decomposed into O and N by electron collision, and further productions such as N2 and NO2 are also found in the discharge. A zero-dimensional reaction model is established, and reveals that most of NO has been transformed into NO2 and N2, with N and O as essential intermediate radicals. In order to improve the NO removing process, the formaldehyde (CH2O) at 1% concentration ratio is added, and the NO removal efficiency has been obviously heightened. NO molecules are transformed into other forms with NO2, N2, CO as major productions and a little of H2O also appeared. The modified main reaction kinetics is evaluated. Furthermore, more CH2O additive have arose out higher NO removal efficiency, due to more radicals of HCO and HNO produced from CH2O for further accelerating the NO removal reactions. CH2O additive is beneficial for NO pollutant gas remediation through the pulse streamer discharge technique.