Acute renal failure is a frequent feature in patients with multiple myeloma (MM). MM-related renal insufficiency may improve after autologous haematopoietic stem cell transplantation (autoHSCT) even in patients initially requiring dialysis. Herein, we report on two unusual cases of late improvement in renal function occurring over more than 5 years after autoHSCT for MM. Clinicians must be aware that slow and progressive improvement in renal function may occur over years in patients with MM-associated renal failure. Our data underline the need for an aggressive treatment, including autoHSCT, in MM patients presenting with severe renal dysfunction.