Periodontitis is a non-specific chronic inflammatory disease caused by plaque biofilm and mediated by host immune imbalance. The prevalence of periodontitis in China is much higher than the global average, so early diagnosis and prognosis monitoring of periodontitis is of great significance. Gingival crevicular fluid (GCF) refers to the fluid that permeates into the gingival sulcus from gingival connective tissue through gingival sulcus epithelium and joint epithelium. Clinical research shows that the change of GCF can reflect the inflammation degree of periodontitis to some extent. Based on literature review and previous work, this paper summarizes the research progress of surface enhanced Raman spectroscopy (SERS) combined with machine learning in early diagnosis of periodontitis by detecting gingival crevicular fluid. This technology is expected to provide a rapid, sensitive, accurate, painless and simple new method for early diagnosis and prognosis monitoring of periodontitis.