Objective:To explore the clinical significance of the expression level of miR-182 in serum exosomes in the infiltration of oral squamous cell carcinoma. Methods:Combined with the TCGA database and related research in the literature,miRNAs highly expressed in exosomes of head and neck squamous cell carcinoma tissues and cell lines were screened. Exosomes were extracted using ExoQuick kit and ultracentrifugationfrom serum and culture supernatant of HEK293 cells,and identified with transmission electron microscopy,nanoparticle tracking analyzer and Western blot;the expression levels of miR-182 in two oral cancer cell lines,HN6,CAL27,and serum exosome were determined by real-time quantitative RT-PCR . The proliferation of CAL27 cells treated with miR-182 antagomir loaded HEK293 cell exosomeswas detected by CCK-8 experiment. Results:miR-182 was highly expressed in the exosomes of head and neck squamous cell carcinoma tissues,oral squamous cell carcinoma cell lines and head and neck squamous cell carcinoma cell lines. The expression levels of serum exosome miR-182 in patients with oral cancer increased,compared with those in the control group. However,the differences were statistically insignificant(P > 0.05). The content of miR-182 in the serum exosomes of patients with tumor infiltration depth >5 mm was significantly higher than that of the control group(P < 0.05). After CAL27 cells were treated with exosomes loaded with miR-182 antagomir,the proliferation ability of CAL27 cells decreased significantly(P < 0.05). Conclusion:miR-182 is highly expressed in oral cancer and the expression level of serum exosome miR-182 is related to the depth of tumor infiltration of oral squamous cell carcinoma. The exosomes loaded with miR-182 antagomir significantly inhibit the proliferation of CAL27 cells.