A comparative analysis of fluorescence spectra of whole blood solution in mice having soybean oil and that in normal mice is conducted through the FLS900 steady-state fluorescence spectrometer. The results show that when using 407 nm laser to stimulate whole blood solution, it will be issued the fluorescence with peaks at 515 nm, 556 nm and 610 nm. The fluorescence intensity of having soybean oil blood less than that of normal blood. Fluorescence polarization is also less than normal polarization of blood. The analysis shows that long-term consumption of soybean oil leads to blood cell surface area smaller that light-emitting area smaller, causing the fluorescence intensity decreases. The volume becomes smaller and enhances the ability of molecular rotation. The ability of launch fluorescence memories′ incident light is decreased and remove polarization effect is obvious enhanced so that fluorescence polarization becomes smaller. The results of the study show that long-term having soybean oil can effectively make human body blood viscosity decrease and improve blood circulation, which provide a reference for people having edible oils correctly.