Niobium(V) oxynitrate is an inorganic compound with the proposed formula NbO(NO3)3.

A single publication claims that niobium(V) oxynitrate is produced by the reaction of niobium pentachloride and dinitrogen pentoxide at 30 °C:[1] Nitryl chloride is produced as a byproduct.

Attempts failed to produce niobium(V) oxynitrate by the reaction dinitrogen tetroxide and niobium pentachloride in acetonitrile in the formation of the acetonitrile niobium dioxide nitrate complex.

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