Abstract: Dongdu weathered coal was oxidized with nitric acid. The structures and properties of the products of nitric humic acid (NHA) were investigated by element analysis and Fourier Transform Infrared Spectra (FT-IR). Effects of catalyst on NHA yield, elemental composition and functional group were discussed. The results show that NHA yields increase apparently with catalyst of H2SO4, H2O2, carbon transition metals supported on carbon nanotubes (CNTs) and solid acid. The contents of carbon, hydrogen and H/C atomic ratio of NHA produced decrease while nitrogen contents and E4/E6 value increase. Nitrogen contents increase apparently in the presence of solid acid or H2SO4. Molecules of NHA produced with catalyst of ferric oxide supported on nickel plating CNTs, nickel supported on CNTs or H2SO4 are smaller. The contents of active functional groups increase significantly with catalyst and the influence is dependent on the kind of catalyst.