Abstract: By using UV-vis, Fourier transform infrared (FT-IR) and the three-dimensional excitation emission matrix fluorescence (3D-EEM) spectroscopies, chemical structures of water dissolved organic matters (DOM) were extracted from typical terrestrial and aquatic plants in or around the Dianchi Lake were investigated. The results showed that characters of UV-visible spectra were similar between the DOMs derived from the terrestrial and the aquatic plants. The ultraviolet absorbance of DOM samples decreased monotonically with increases of the wavelength. The SUVA₂₅₄ values of DOM derived from terrestrial plants were greater than those from aquatic plants, which indicated the higher humification degree of the DOM from the terrestrial. Ratios of A₂₅₀ and A₃₆₅ of the leaf DOMs were less than those of the stems, which illustrated that both aromaticity and molecular weight of leaf DOMs were higher than those of stem DOMs. The characteristic peaks of —COO^-, —CH₂, —CO, —OH and —NH₂ were clearly shown in DOMs for both terrestrial and aquatic plants, and suggested that they would be the main function groups in DOMs of these species. The 3D-EEM spectrum showed that the DOMs from stems of the terrestrial plants contained fulvic acid and those from leaves have humic acid for these species. DOMs of stems and leaves of aquatic plants mainly contained fulvic acid, except the water hyacinth which had humic acid in its DOM. Except for the water hyacinth, DOMs from stems of all plants contained the tryptophan-like organic matters, but there were no similar fluorophore showed in their leaf DOMs.