Cytomegalovirus retinitis (CMVR) following hematopoietic stem cell transplantation (HCT) for a primary immunodeficiency is a rare but highly morbid condition with potential irreversible consequences despite optimal antiviral pharmacotherapy. Viral-specific T cells (VSTs) pose a promising and safe approach eradicating intractable viral disease. We describe the case of a 21-month-old male with Wiskott-Aldrich syndrome (WAS) and CMVR post-HCT with sustained long-term virologic and clinical response after CMV-specific T cell therapy. This case highlights the need to consider VSTs as an adjunct upfront strategy in refractory CMVR and for routine ophthalmologic screening and surveillance in high-risk patients post-HCT.