Introduction: Splenectomy had been previously performed in ABO-incompatible kidney transplantation to reduce the B cell pool. However, studies have shown that patients undergoing splenectomy may have a lifelong susceptibility to infection and mortality. Splenectomy may affect the incidence of cytomegalovirus (CMV) disease even at a very late stage after transplantation in ABO-incompatible recipients. Patients and Methods: Seven patients received their graft from an ABO-incompatible living donor at our institution and underwent splenectomy for B cell reduction. Among them, 3 recipients experienced very late-onset CMV disease approximately 10 years after their transplant and were enrolled in this study. Results: Very late-onset CMV disease occurred at 9 years and 9 months, 15 years, and 13 years and 5 months after transplantation, respectively. Two recipients suffered from CMV retinitis, while one experienced colitis. The age of the patients at onset of CMV disease was 69 years, 42 years, and 71 years, respectively. Conclusion: This may be the first report on very late-onset CMV disease after splenectomy in ABO-incompatible kidney transplantation. We should be aware that these recipients can experience very late-onset CMV disease even approximately 10 years after their transplant.