OBJECTIVE：To stud y the effects of sinapine thiocyanate （ST） on the proliferation ，epithelial mesenchymal transformation（EMT）and metastasis of human cutaneous squamous cell carcinoma SCL- 1 cells，and to investigate its possible mechanism. METHODS ：Human cutaneous squamous cell carcinoma SCL- 1 cells were divided into blank control group （0.1％ DMSO） and ST different concentration groups （5，10，20 μmol/L）. CCK- 8 assay，5-ethynyl-2′-deoxyuridine（EDU）test， scratch test and Transwell chamber invasion test were adopted to test the proliferation ，migration and invasion ability. The expression of N-cadherin and E-cadherin were detected by Western blot and immunofluorescence assay . Other SCL- 1 cells were collected and divided into blank control group （0.1％ DMSO），ST group （20 μmol/L），ST+NSC228155 group [ 20 μmol/L ST+100 μmol/L NSC228155（EGFR agonist ）] and ST+SC 79 group [ 20 μmol/L ST+20 μmol/L SC79（PI3K/Akt agonist ）]. The proliferation ，migration and invasion ability of SCL- 1 cells in each group were detected by CCK- 8 assay，scratch test and Transwell chamber invasion assay. The expression of epidermal growth factor receptor （EGFR），phosphatidylinositol 3 kinase（PI3K），phosphorylated phosphatidylinositol 3 kinase（p-PI3k），protein kinase B （Akt）and phosphorylated protein Akt （p-Akt）protein of cells in blank control group and ST different concentration groups（5，10，20 μmol/L）were determined by Western blot assay so as to validate the relationship between ST effect and EGFR/ PI3K/Akt signaling pathway. SCL- 1 cells and human normal skin fibroblasts cell WS 1 were divided into blank control group （0.1％ DMSO），ST group （20 μmol//L），ZD1839 group（positive control ，20 μmol//L，EGFR inhibitor ）and LY 294002 group（positive control，20 μmol//L，PI3K/Akt inhibitor ）. CCK- 8 assay was used to detect the cell proliferation in order to evaluate the cells cytotoxicity of ST. RESULTS ：Compared with blank control group ，the proliferation ，migration and invasion ability of SCL- 1 cells were significantly decreased in 5，10，20 μmol/L ST groups（P＜0.05）. Western blot and immunofluorescence assay showed that the expression of N-cadherin in SCL- 1 cells were decreased significantly in 5，10，20 μmol/L ST groups（P＜0.05），while the protein expression of E-cadherin was increased significantly （P＜0.05）；the protein expressions of EGFR ，p-PI3K and p-Akt were significantly decreased （P＜0.05）. Compared with ST group ，the proliferation ，migration and invasion ability of SCL- 1 cells were increased significantly in ST + NSC 228155 group and ST + SC 79 group （P＜0.05）. Compared with blank control group ，the proliferation ability of WS 1 cells had no significant change in ST group ，while the proliferation ability of SCL- 1 cells was decreased significantly （P＜0.05）；the proliferation ability of the two kinds of cells were decreased significantly in ZD 1839 group and LY 294002 group（P＜0.05）. Compared with ST group ，the proliferation ability of WS 1 cells was decreased significantly in ZD1839 group and LY 294002 group（P＜0.05），but there was no significant difference in the proliferation ability of SCL- 1 cells （P＞0.05）. CONCLUSIONS ：ST may inhibit the proliferation ，EMT and metastasis of SCL- 1 cells through inhibiting the activation of EGFR/PI 3K/Akt signaling pathway ，and its side effects are few.