Backgroun：Esophageal cancer is insidious, with recurrent metastasis and chemotherapy resistance as primary reasons for treatment failure. Recent interest has focused on the molecular mechanisms of tumor-associated macrophages (TAMs) in the tumor microenvironment, which remain largely unknown. Methods：TAMs were examined using both in vitro and in vivo assays. Seventy-seven normal paracancerous tissues and esophageal squamous cell carcinoma (ESCC) tumor samples were compared using immunohistochemical methods. Molecular mechanisms were identified using Transwell, Western blotting, Fluorescence-assisted cell sorting, CCK 8, and reverse transcriptase–polymerase chain reaction assays. Results: M2 TAMs were significantly elevated in ESCC tissues. M2 TAMs contributed to ESCC development and resistance to treatment both in vitro and in vivo. Elevated CD163 + TAMs in patients with ESCC correlate with an unfavorable prognosis. We found that TAMs release macrophage migration inhibitory factor (MIF), which regulates the expression of B-cell lymphoma 2 (Bcl-2), P-glycoprotein 1 (P-gp), and Bcl-2 associated X (Bax) to promote drug resistance and stimulate phosphoinositol 3-kinase (PI3K)–protein kinase B (AKT) signaling. Conclusion:Our findings demonstrate that MIF performs a functional role in the macrophage-mediated resistance of ESCC cells to cisplatin and that targeting MIF may serve as a strategy for molecular therapy.