An experimental setup is established for measuring ultraviolet-visible(UV-VIS) micro-fluorescence-spectra of single oil inclusion by integrating elements, such as inverted microscope, reflecting microscopic objective, micro-lens, fiber and spectrometer. Any rebuilding to the microscope is not needed to be done. The UV-VIS spectra of single oil inclusion of Fu 4 well（Quan 3 stratum, Jilin oil field）are measured. By fluorescence spectra excited at 250 nm, the main aromatic hydrocarbon composites of the paleo-oil are qualitatively determined. The results show that the relatively heavy hydrocarbons in liquid oil inclusions are more than that in the gas-liquid inclusions. By fluorescence spectra excited at 365 nm, the chromaticity diagram of the oil inclusions are calculated, which overcomes the subjectivity of judging the colors by human eyes. The UV-VIS spectra and chromaticity diagram of the single oil inclusion from same stratum show that there maybe two maternal sources of different maturities when the secondary oil charges.