Wistar rats were divided into 3 groups. A single dose of 125, 250, 500 mg/kg of fructose 1,6 diphosphage (FDP) Mg were given by intravenous drop. Serial blood samples were collected at designed time points. The plasma FDP concentration was measured by using enzymology method and the plasma Mg 2+ concentration was detected by atomic absorption spectrophotometry (AAS). After intravenous drop of single dose, the plasma concentration versus time curves of Mg 2+ conformed to two compartment model. T 1/2α was 12.01~16.9 min, T 1/2β was 103.59~118.46 min and Vd was 1.61~1.78 L/kg. The main parameters, including CL, T 1/2el , V ss , and AUC/X 0 , appeared to be dose independent. The characters of the C T curves of FDP were different from that of Mg 2+ . Non compartment model was used to calculate the main pharmacokinetic parameters of FDP. T 1/2el was 8~10 min. MRT was 19~22 min and CL was 0.011~0.031 L·kg -1 ·min -1 . FDP was eliminated linearly. AUC and C max were increased in a dose proportional manner. The difference of the parameters between FDP and Mg 2+ suggested that FDP Mg could be divided into two parts, FDP and Mg 2+ , and then, they could be eliminated from the organism according to their own routes respectively.