Wiskott-Aldrich syndrome (WAS) is a severe disorder characterized by thrombocytopenia, eczema, immunodeficiency, and increased risk of autoimmune disease and lymphoid malignancies. The immunodeficiency caused by a lack of WAS protein expression has been mainly attributed to defective T-cell functions. Whether WAS mutations differentially influence the T-cell receptor (TCR) diversity of different T-cell subsets is unknown.We aimed to identify the degree and pattern of skewing in the variable region of the TCR β-chain (Vβ) in different T-cell subsets from patients with WAS.The TCR repertoire diversity in total peripheral T cells, sorted CD4 + and CD8 + T cells, and CD45RA + (CD45RA + CD45RO − cells) and CD45RO + (CD45RA − CD45RO + cells) CD4 + and CD8 + T cells from patients with WAS and age-matched healthy control subjects was analyzed and compared by using spectratyping of complementarity-determining region 3. The complementarity-determining region 3 of TCRβ transcripts in CD45RA + CD4 + and CD45RA + CD8 + T cells, CD45RO + CD4 + T cells, CD8 + terminally differentiated effector memory T (Temra) cells, and naive CD8 + T cells (CD8 + CD45RO − CCR7 + cells) from patients and control subjects were analyzed and compared by using high-throughput sequencing.The TCR repertoire diversity in CD45RO + CD4 + T cells and CD8 + Temra cells of patients with WAS was significantly skewed in comparison with that seen in age-matched control subjects.Our results indicate that WAS gene mutations selectively influence TCR repertoire development or expansion in CD45RO + (memory) CD4 + T cells.