Background The causative virus of coronavirus disease 2019 (COVID-19) may cause severe fatal pneumonia. The clinical presentation includes asymptomatic infection, severe pneumonia, and acute respiratory failure. Data pertaining to acute renal injury due to COVID-19 in patients who have undergone renal transplantation are scarce. We herein report two cases of COVID-19 along with acute kidney injury following kidney transplantation. Case presentation: Two patients with COVID-19 underwent renal transplantation and were subsequently diagnosed with acute kidney injury. The first patient presented with progressive respiratory symptoms and acute renal injury. He was treated with diuretics and suspension of immunosuppressive therapy; however, the patient died. The second patient presented with respiratory tract symptoms, hypoxemia, and progressive deterioration of renal function followed by improvement. Her mycophenolate mofetil was stopped after admission, and tacrolimus was discontinued 10 days later. Moxifloxacin and methylprednisolone were continued in combination with albumin and gamma globulin infusion. A diuretic was administered, and prednisone was gradually reduced along with tacrolimus. The patient exhibited a satisfactory clinical recovery. Conclusion Patients who develop COVID-19 after kidney transplantation are at risk of acute kidney injury, and their prednisone, immunosuppressant, and gamma globulin treatment must be adjusted according to their condition.