The spectrum of excited N2 molecules and ions was measured by optical emission spectroscopy in pulsed corona discharge with a wire-to-plate reactor. The ratio of emission intensities emitted by the excited molecules and ions of N2 was compared with numerical simulation to determine average electron energies and electric field distributions. Within 2 cm distance from wire electrode in horizontal and vertical directions, electric field and average electron energies appear to be in the ranges of 11.05~19.6 MV·m-1 and 10.10~13.92 eV respectively; as the distance increases, average electron energies and electric field show a similar trend: first decrease and then increase. Chemically active species, such as OH, O and O3, can be generated through the energetic electron collisions with H2O and O2 directly or indirectly. For the NO oxidation, there is no coexistence of NO and O3, whereas there is a coexistence of NO and OH. NO is oxidized by O3 or O more efficiently than by OH radical.