A 49-year-old man had infected falciparum malaria during a tour of tropical countries. His symptoms were severe; a high fever and anemia developed and the platelet count decreased. The patient well responded to an antimalarial agent and no Plasmodium had been isolated in the peripheral blood in 18 days. He recovered from malaria, but complained of a right hypochondralgia about one week later. Abdominal ultrasonography revealed hypertrophy of the gallbladder wall and filled debris. A diagnosis of acute cholecystitis was made and a cholecystectomy was performed. Severe inflammation was seen in the vicinity of the gallbladder and its lumen was filled with mucous and black debris. It is thought that indirect reacting bilirubin, which was a metabolite of hemoglobin treated in the reticuloendotherial system due to massive acute hemolysis, was converted to the direct reacting bilirubin in the liver which was excreated into the biliary duct and reabsorbed water in the gallbladder to form debris, causing acute cholecystitis.