The interaction between antibacterial olaquindox (OLA) and bovine serum albumin (BSA) was studied by fluorescence spectroscopy and UV-vis absorption spectroscopy.Spectroscopic analysis of the emission quenching at different temperatures indicated that the quenching mechanism of BSA by OLA was static quenching.Quenching constants and thermodynamic parameters at different temperatures were calculated.The binding was mainly due to electrostatic force.The distance between BSA and OLA was calculated to be 3.8 nm based on the F(o)rsters none radioactive energy transfer theory.Furthermore, the configuration of BSA in the presence and absence of OLA were studied by synchronous fluorescence spectra and three dimensional fluorescence spectra, indicating that it was basically the same.Docking study involved a BSA crystal model created by us confirmed all the results above.