ABSTRACT: Wiskott-Aldrich syndrome (WAS) is a disorder characterized by rare X-linked genetic immune deficiency with mutations in the was gene, a gene expressed specifically in hematopoietic cells, and the spleen plays a major role in hematopoiesis and the clearance of red blood cell. However, till now, comprehensive analyses of the spleen between wild type (WT) and WASp-deficient (WAS-KO) mice, especially at the transcriptomic level, have not been studied. Here, single-cell RNA sequencing (scRNA-seq) was adopted to identify various types of immune cells and investigate the mechanism of immune deficiency. We identified 30 clusters and 10 major cell subtypes among 11, 269 cells, including B cell, T cell, dendritic cell (DC), Natural Killer (NK) cell, monocyte, macrophage, granulocyte, stem cell and erythrocyte. Meanwhile, we evaluated the gene expression differences of cell subtypes, and analyzed the differential gene expression (DEGs) and enrichment analyses to reveal the reasons for the dysfunction of these different cell populations in WAS. Furthermore, some key genes were screened out by comparing the DEGs of each cell type during specific and non-specific immunization, and further analysis showed that these key genes were newly discovered pathologically related genes in WAS-KO mice. In summary, we present a detailed single cell resolution landscape of immune cells in spleen of WAS-KO mice. These unprecedented data uncovered the transcriptional characteristics of specific and non-specific immune cells, and the key genes were identified to lay a foundation for future studies of WAS, especially in discovering novel and underexplored mechanisms to improve gene therapies for WAS.