Graft-versus-host disease (GVHD) after pancreas transplantation is a rare but serious complication: All previously reported cases were fatal. We herein report three cases of GVHD after pancreas transplantation with favorable outcomes. Patients with a history of kidney (and pancreas) transplantation subsequently received a pancreas (and kidney) transplantation (i.e., pancreas retransplantation or pancreas after kidney transplantation) and developed acute GVHD. All of them responded to increased immunosuppression (e.g., steroid bolus, antithymocyte globulin) and retained normal graft function. Because the clinical manifestations are non-specific, vigilance is necessary to make an accurate diagnosis. We underscored the importance of a biopsy of involved organs and the clinicopathologic correlation in the early diagnosis of GVHD. Augmented immunosuppression to prevent progression from a self-limited disease to life-threatening pancytopenia or sepsis may be most critical to improve outcome.