The effect of sodium dichromate on cellular metabolism was investigated. Intraperitoneal injection of sodium dichromate into the rat (20 or 40 mg/kg) caused significant increases in serum lactate, pyruvate, and creatinine concentrations within 15 min after intoxication. Severe hyperglycemia occurred thereafter, as a result of increased hepatic glycogenolysis, which was seen in the first 2 h after dichromate. However, liver glycogen was resynthesized in 24 h-fasted rats after glucose refeeding. Dichromate decreased serum total amino acids, with a consequent increase in blood urea nitrogen (BUN) concentration. Unlike HgCl2 (2 mg/kg, i.p.), As2O3 (5 mg/kg, i.p.), and KCN (5 mg/kg, i.p.), dichromate showed the largest metabolic disturbance only in the early period after treatment. In addition, dichromate produced cyanosis, which appeared during the period of the accelerated glycolysis and breakdown of creatinine phosphate. Regardless of chemical species, only the hexavalent chromium compounds had an effect on the cellular metabolism. Trivalent chromium compounds had no effect at all. These results suggest that dichromate possesses a characteristic dual action on cellular metabolism, which might be related to its metabolic fate.