Rapid, non-destructive analysis of the milk by Raman Spectroscopy is used in different analyses and has enabled the determination of biological samples without using additional chemicals. In the study, it is aimed to investigate the molecular structures of normal and mastitic milks using Raman spectroscopy by application of Surface Enhanced Raman Spectroscopy (SERS) method and this study is the first study done for this purpose. In the study, the presence or absence of functional groups of the spectra obtained from the milk samples was compared with the reference spectra in other studies. It was observed that the peaks obtained from the biochemical structures of normal and mastitic milks were consistent with the literature. In addition, it was found that the biochemical components (such as fat, proteins, carbohydrates and minerals) of subclinical mastitis and normal milk did not change at the molecular level. It was thought that there was no change at the molecular level as there was no visible deterioration in the milk with subclinical mastitis and the factor caused by the infection in the breast tissue.