About 5-10% of patients with myasthenia gravis concomitantly have other autoimmune diseases. However, the coexistence of myasthenia gravis and pernicious anemia is rare. Here, we report a 73-year-old Taiwanese woman who developed myasthenia gravis 5 months after the onset of pernicious anemia. Her myasthenic and pernicious anemia symptoms markedly improved after pyridostigmine, prednisolone and hydroxocobalamine treatment. It is important to recognize concurrence of myasthenia gravis and pernicious anemia in the same patient because the therapeutic results for both diseases are rewarding.