Semiacute toxicity of cola fluid, Coca-Cola, conducting for approximately a month in rats, was studied. A trend of cariogenicity of Coca-Cola was strongly indicated. When the fluid was given ad libitum, decarbonized Coca-Cola and carbohydrate solution, consisted 8% of glucose and 3.5% of sugar and then adjusted pH to 2.4 with oxalic acid, were consumed 2 to 3 times greater than the control (water). A hyperuresis was observed as the result of great consumption of liquid, but no liver nor kidney degeneration was observed by histopathological examination. The diet consumption of the groups of Coca-Cola and carbohydrate solution was approximately a half of the control, water. However, when a complete diet was given, no physiological difference in time was observed, except in diarrhea and depression of hair gloss in Coca-Cola group.