Although glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzyme disorder worldwide, it has rarely been reported among Korean. The patient was previously healthy 39 yr old male who showed severe hemolytic anemia and acute renal failure accompanied by hyperbilirubinemia after hepatitis A infection. The additional studies for differential diagnosis of hemolytic anemia showed a moderate deficiency of G6PD enzyme. Because hepatitis A infection in patient with G6PD deficiency present much more severe clinical symptoms, G6PD enzyme should be examined in patients with triggering factors of hemolysis such as hepatitis A infection.