To evaluate immune cell infiltration in ES, we applied the deconvolution method to analyze ES expression data and found that memory B cells and activated NK cells had higher infiltration in the high-risk group than in the low-risk group, and that Tregs, activated CD4 memory T cells, activated dendritic cells, M2 macrophages, monocytes, resting mast cells, and γδ T cells were significantly related to ES prognosis. Here, CD4 is linked to Ewing sarcoma.