Based on fluorescence and absorbance spectroscopy, the photophysical properties and mechanisms of novel organic europium (Ⅲ) complexes in the case of different concentration in ethanol solution and solid flour were studied at room temperature. It was found that the complex absorption spectra are mainly due to the Phenanthroline ligand, gradually exhibit saturated absorption from shortwave to long wave with the concentration increased, and stretch and broaden to long wave. And four characteristic peaks of the fluorescence spectra are all emission spectra of Eu3+ in the complex, and the strongest emission wavelength was 617 nm corresponding to the ５Ｄ０→７Ｆ２ transition of Eu3+. And then, it is presented that the perturbation of acetanil ligand changes the parity state of Eu3+ energy field, resulting in the increase of ５Ｄ０→７Ｆ２ transition probability, making phenanthroline transfer its energy absorbed to Eu3+, and inducing 617nm strong emission of fluorescence peak.