Melamine is a kind of small molecule compound, which has been illegally adulterated in dairy food because of the rich nitrogen content and stable chemical properties. Therefore, the detection of melamine is of great significance to food safety and human's health protection. Melamine can emit weak fluorescence, making it difficult to detect melamine directly. However melamine can significantly enhance the emission of the tetracycline-europium (EuTC) complex at a wavelength of 616 nm, hence this work uses EuTC complex as a fluorescent probe to detect melamine. According to the characterizations of absorption spectra, molecular electrostatic potential distribution and the time-resolved spectra, we speculated that tetracycline and melamine may form a complex through hydrogen bonding interaction, causing the melamine closer approach to Eu3+ and reducing the non-radiative energy loss of water molecules to EuTC complex, which significantly enhanced the fluorescence intensity of EuTC. The fluorescence intensity with melamine concentration in the range of 0.5~40 Î¼M shows a good linear relationship, and the correlation coefficient is 0.9951 with the detection limit of 0.0785 Î¼M, which shows a high sensitivity in detection of melamine. As far as we know, EuTC complex is the first time that has been used as a fluorescent probe to detect melamine, which provides a supplement and extension for the detection of melamine in fluorescence spectroscopy.