Graft-versus-host-disease (GVHD) is a complication of solid organ transplantation, most commonly of the small bowel or liver. Herein, we have presented a case of GVHD in a 27-year-old man who underwent an human leukocyte antigen (HLA) minor mismatch renal transplantation from his father. After the procedure, the patient presented with a fever, skin rash, and watery diarrhea. An allograft kidney biopsy demonstrated no sign of rejection; however, anti-A antibody was detected in plasma and progressive anemia was attributed to hemolytic anemia owing to a passenger lymphocyte syndrome. From those findings, we suspected that the clinical symptoms were caused by acute GVHD. An endoscopic biopsy of the colon revealed apoptotic cells consistent with the disease. We found reports of only 5 other GVHD cases after kidney transplantation. Several risk factors are associated with GVHD, such as transfer of graft lymphocytes, donor HLA homozygosity, and a relationship between recipient immunogenicity and immunosuppression. In this case, detection led to early diagnosis of donor-derived GVHD due to passenger lymphocyte syndrome. It is important keep GVHD in mind and to understand its risk factors as the mortality rate is high.