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We have observed excimer fluorescence spectra of fluorenone in steady state excitation at 308 nm in both polar and non-polar solvents at room temperature. In addition to the monomer fluorescence band in the region of 340-355 nm, we have also observed another fluorescence band at longer wavelengths in the region 480-510 nm in all the solvents with concentration variation. The fluorescence lifetime measurements of these bands of fluorenone in the solvents Benzene and Acetonitrile revealed that the longer wavelength band with shorter lifetime is to be due to the formation of excimer. Combining our results of steady state fluorescence and the measurement of fluorescence lifetimes of monomer and excimer with the reported [1] studies of laser induced fluorescence, the mechanism of excimer formation has been established to be due to the Triplet-Triplet annihilation. The details for the formation of excimer and its mechanism will be presented.