Accurate detection of low concentration methanol and ethanol in alcohol is of great importance. Low frequency Raman spectroscopy is one of the most effective methods to study intermolecular interactions in liquid phase. In this letter, a novel ultra-low frequency Raman spectroscopy was designed to study ethanol and ethanol methanol mixture with different concentrations. It was found that there were two Raman characteristic peaks at 78 cm-1 and 170 cm-1 for ethanol solution at different concentrations, and two characteristic peaks at 85 cm-1 and 178 cm-1 for ethanol methanol mixture at different concentrations, of which 78 cm-1 and 85 cm-1 were caused by H-OH vibration, while 85 cm-1 and 178cm-1 were caused by C-OH bond vibration. At the same time, we found the dependence of the above ultra-low frequency Raman peak frequency on the concentration of ethanol and ethanol methanol mixture, which can provide an innovative experimental idea and basis for the accurate identification of lower concentration ethanol and methanol solutions.