OBJECTIVE: To study the correlation between immune cell infiltration in colorectal cancer tissue and clinical prognosis and to explore the levels of some immune cell genes for predicting the prognosis of patients with glioma colorectal cancer. METHODS: In this study, we extracted colorectal cancer data from the cancer genome atlas (TCGA). Based on a deconvolution algorithm (called CIBERSORT) and clinically annotated expression profiles, the analysis assessed the infiltration patterns of 22 immune cells in colorectal cancer tissue to determine the association between each cell type and survival. Differences in five-year survival rate effectively illustrate the clinical prognostic value of each immune cell proportion in colorectal cancer, using a bar graph, correlation-based heatmap to represent the proportion of immune cells in each colorectal cancer sample. RESULTS: A total of 473 colorectal cancer tissues and 41 normal control tissues were extracted from the TCGA database, and the comparative analysis showed that there were differences in the proportion of various TIICs in colorectal cancer tissues, which could characterize individual differences and have prognostic value. Among the cell subsets studied, the proportions of memory B cells, plasma cells, CD4+ T cells, natural killer (NK) cells, M0 macrophages, M2 macrophages, and activated mast cells were significantly different between normal and cancer tissues. Resting NK cells, CD8+ T cells, and plasma cells were associated with T phase, activated dendritic cells were associated with N phase, and eosinophils, M1 macrophages, and activated mast cells were associated with M phase. Survival analysis showed that activated dendritic cells were positively associated with five-year survival rate in colorectal cancer patients. Naive CD4+ T cells were inversely associated with five-year survival rate. CONCLUSION: There are different degrees of immune cell infiltration in colorectal cancer tissues, and these differences may be important determinants of prognosis and treatment response. We conducted a new gene expression-based study of immune cell subtype levels and prognosis in colorectal cancer, which has potential clinical prognostic value in colorectal cancer patients.