Esophageal squamous-cell carcinoma (ESCC), one of the most prevalent and lethal malignant disease, has a complex but unknown tumor ecosystem. Here, we decipher for the first time the full compositions of ESCC tumor based on analyzing 208,659 single-cell transcriptomes in ESCC derived from 60 individuals. We identify 8 essential expression programs from malignant epithelial cells and discovered 43 cell types including 26 immune cell and 17 nonimmune stromal cell subtypes in the tumor microenvironment (TME), and also explicate the interactions between cancer cells and other cells and the interactions among different cell types in the TME. Moreover, we have linked the cancer cell transcriptomes to the somatic mutations and identified several markers significantly associated with survival time in patients, which may be relevant to precision cares of ESCC patients. These results renew our understanding of ESCC and provide a valuable example and resource for investigating other types of solid tumor.