Tumor immune microenvironment (TIME) of colon cancer (CC) shows quite a lot immune cell infiltration (IMI), and have been identified to be extensively drawn into the evolution of CC. Accumulated evidence demonstrated that plasma cells (PC) play an extremely significance role in advance of antitumor immune. Nonetheless, comprehensive analysis of PC infiltration in clinical prognosis and immunotherapy was poor in CC. This reasearch systematically addresses the gene expression model and clinical information of colon cancer patients (CCP) downloaded from the TCGA (The Cancer Genome Atlas) and GEO (Gene Expression Omnibus) databases in the current study. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), GSVA, and the MAlignant Tumors using Expression data (ESTIMATE) algorithm were employed to research the potential mechanism and pathways. Immunophenoscore (IPS) was executed to evaluate immunotherapeutic significance of risk score (RS). Half maximal inhibitory concentration (IC50) of chemotherapeutic medicine was predicted by employing the pRRophetic algorithm. Herein, 513 CC samples (including 472 tumor samples and 41 normal samples) were collected from TCGA-GDC database. Significant black module and 313 candidate genes were considered as PC-related genes by accessing WGCNA. Five pivotal genes were established through multiple analysis, which perform excellent prognostic. Then, we futher to explored underlying correlation between RS with tumor mutation burden (TMB). In addition, RS obviously correlated with various of tumor immune microenvironment (TIME). Different risk CC samples showed various signaling pathways activity and pivotal different sensitivities to administering chemotherapy. At the end, the biological roles of CD177 gene were uncovered in CC.