BACKGROUND INFORMATION: Delayed graft function (DGF), defined as the need for dialysis within the first week of a kidney transplant, is a common complication, particularly in extended criteria donor transplants, where its incidence ranges from 21 to 31%. OBJECTIVES: We observed a prolonged case of DGF in a 47-year-old patient with chronic kidney disease (CKD) resulting from diabetic nephropathy. The patient, classified in a moderate immunologic mismatch group, received a marginal deceased donor kidney. RESULTS: For the first 4 weeks post-transplantation, graft function was impaired. After 29 days of anuria, the transplanted kidney began to recover. The literature review found few clinical cases of DGF extending beyond 1 month. Our patient had several risk factors for DGF, including diabetes mellitus, pre-transplant hemodialysis, and moderate immunologic mismatch. Additionally, the marginal graft increased the risk of ischemia-reperfusion injury and glycocalyx damage. However, it remains unclear how these factors influenced the duration of DGF. The exact cause of the extended DGF in this case remains unknown. Although the literature identifies key risk factors for DGF, data on factors leading to prolonged kidney dysfunction are lacking. Therefore, decisions to remove a non-functioning transplanted kidney should not be made hastily.