Due to the wide range of Lactoperoxidase (LPO) application in the food production and medicine, stabilization of this enzyme seems to be necessary. In this study, different methods, such as fluorescence spectroscopy, FTIR spectra, docking studies, and enzyme activity assay were used to investigate the effects of hydroxyectoine on the stability and structure of LPO. Results presented that hydroxyectoine improved the catalytic activity of LPO. FTIR and UV-visible spectra studies confirmed that hydroxyectoine bonded to the LPO. Fluorescence spectroscopy revealed that hydroxyectoine quenched the LPO fluorescence. Thermodynamic parameters and molecular docking demonstrated that hydrogen bonding and van der Waals forces were major forces, besides increased enzyme Tm. In summary, hydroxyectoine increased LPO activity and stability through changing secondary structures of the enzyme.