In order to develop covalent organic frameworks (COFs) with strong π-π conjugation effect, excellent photocatalytic performance and high photocatalytic oxygen evolution reaction (OER) activity, the N,N'-p-acetonitrile benzene-3,4,9,10-naphthalimide and 1,3,5-tris(p-formylphenyl)benzene were used as monomers to synthesize sp2-carbon-linked and hexagonal NP-COF by solvothermal method. Encouragingly, NP-COF was confirmed to be an excellent semiconductor photocatalytic catalyst with good light absorption performance, good carrier generation and mobility by structure, morphology and photoelectric performance characterization. It could efficiently catalyze the oxidation reaction of water molecules under visible light, and the average oxygen production rate reached 344 μmol/(g·h) with 7.4 mg Co(NO3)2?6H2O as a co-catalyst.