To evaluate the functional consequences of elevated PAI‐1, we applied a PAI‐1 inhibitor and found that the inhibition of PAI‐1 conspicuously prevented TSA‐induced ESCC cell migration, EMT, upregulation of E‐cadherin, and downregulation of β‐catenin and vimentin, but did not inhibit TSA‐induced upregulation of Slug, indicating that the upregulation of PAI‐1 is linked with TSA‐mediated ESCC cell migration via promotion of EMT, which is not related to the alteration of Slug level. The gene discussed is SNAI2; the disease is esophageal squamous cell carcinoma.