In the present paper, recent applications of a resonant multiphoton ionization photoelectron technique to the study of autoionization of NO molecule are demonstrated in the following three cases: (a) autoionization occurring by (2 + 1) resonant excitation via Rydberg A state, (b) autoionization occurring by (2 + 1) resonant excitation via valence B state, and (c) autoionization occurring by (2 t 1) resonant excitation via higher valence B' state.