Aim To explore the characteristics of immune microenvironment of atherosclerosis based on the bioinformatics method of single cell transcriptome, and to explore the potential relationship between immune inflammation and atherosclerosis. Methods Single cell transcriptome data set GSE159677 was extracted from the GEO database to visually analyze the cellular components of carotid atherosclerotic plaque and its adjacent non-plaque area. CellChat was used to integrate intercellular communication networks, analyze the difference in intercellular interaction, identify the difference in the immune inflammatory signal pathway of atherosclerotic plaque, and explore the specific change pathway of intercellular receptor-ligand in the atherosclerotic immune microenvironment. Results In this study, the cellular composition, and cellular communication in atherosclerotic plaques were analyzed from the perspective of single cell sequencing. It was found that in the cellular composition of atherosclerotic plaques, endothelial cells and smooth muscle cells decreased, while T cells, monocytes, macrophages, and chondrocytes increased significantly. Through the analysis of cellular communication, it was found that there were significant changes in the communication between dendritic cells, monocytes, macrophages, natural killer cells, and endothelial cells, and between some cells and monocytes, including CXCL family and ACRK1, CCL family and ACRK1, MIF and CD74 and other ligand-receptor interactions. The communication of MIF, ANXA1, YNF, RETN, and LGASL9 to monocytes and the communication of NAMPT, CCL2, and TNFSF12 to endothelial cells play an important role in the immune inflammatory response regulating the development of atherosclerosis. Conclusion Immune inflammatory microenvironment plays an important role in the formation of atherosclerotic plaque.