Though therapy that promotes anti-tumor response about CD8 + tumor-infiltrating lymphocytes (TILs) has shown great potential, clinical responses to CD8 + TILs immunotherapy vary considerably, largely because of different subpopulation of CD8 + TILs exhibiting different biological characters. To define the relationship between subpopulation of CD8 + TILs and the outcome of antitumor reaction, the phenotype and function of CD103 + CD8 + TILs in esophageal squamous cell carcinoma (ESCC) were investigated. CD103 + CD8 + TILs were presented in ESCC, which displayed phenotype of tissue-resident memory T cells and exhibited high expression of immune checkpoints (PD-1, TIM-3). CD103 + CD8 + TILs were positively associated with the overall survivals of ESCC patients. This population of cells elicited potent proliferation and cytotoxic cytokine secretion potential. In addition, CD103 + CD8 + TILs were elicited potent anti-tumor immunity after anti-PD-1 blockade and were not affected by chemotherapy. This study emphasized the feature of CD103 + CD8 + TILs in immune response and identified potentially new targets in ESCC patients.