IgM nephropathy presents with refractory nephrotic syndrome and its treatment is a significant challenge for pediatricians. We present two patients with IgM nephropathy and frequently relapsing nephrotic syndrome treated with rituximab and subsequently mycophenolate mofetil. Both showed complete remission, which 24 to 30 months later, was still maintained. The role of mycophenolate mofetil therapy in maintaining remission after successful treatment of rituximab in IgM nephropathy needs to be examined.