The pink powder of manganese L-threonate was obtained by extracting with alcohol the concentrated solution derived from the reaction between L-threonic acid solution prepared by double decomposition reaction of calcium L-threonate with oxalic acid and superfluous manganese oxide at 80℃for c ertain time.The composition of the n ew compound was determined by chemical and elemental analyses and its formu la fits Mn (C 4 H 7 O 5 ) 2 ·H 2 O,the IR spectra indicated that Mn 2+ in the compound coordinates to oxygen atom of the carboxyl group,while th e proton of the carboxyl group is dissociated,i t was assumed that the coordination n umber of Mn 2+ was 4.The results of TG-DTG showed that the compound have fairish stability,the intermediate and final product of the thermal de-composition of the compound are Mn (C 4 H 7 O 5 ) 2 and MnO 2 ,respectively.The constant volume combustion energy of the compound,Δ c E,were determined by a precise rotating-bomb calorimeter at 298.15K,it was(-3384.30±1.21)kJ·mol -1 ,its standard enthalpy of Combustio n,Δ c H m ,and standard enthalpy of formation,Δ f H m ,were calculated.They are(-3383.07±1.21)kJ·mol -1 and(-2571.68±1.63)kJ·mol -1 ,respectively. The pink powder of manganese L-threonate was obtained by extracting with alcohol the concentrated solution derived from the reaction between L-threonic acid solution prepared by double decomposition reaction of calcium L-threonate with oxalic acid and superfluous manganese oxide at 80 ° C. for c ertain time. The composition of the ew compound was determined by chemical and elemental analyzes and its formu la fits Mn (C 4 H 7 O 5) 2 .H 2 O, the IR spectra indicated that Mn 2+ in the compound coordinates to oxygen atom of the carboxyl group, while th e proton of the carboxyl group is dissociated, it was assumed that the coordination n umber of Mn 2+ was 4. The results of TG-DTG showed that the compound have fairish stability, the intermediate and final product of the thermal de-composition of the compound are Mn (C 4 H 7 O 5) 2 and MnO 2, respectively. constant volume combustion energy of the compound, Δ c E , were determined by a precise rotating-bomb calorimeter at 298.15 K, it was (-3384.30 ± 1.21) kJ · mol -1, its standard enthalpy of Combustio n, Δ c H m, and standard enthalpy of formation, Δ f H m, were calculated. They are (-3383.07 ± 1.21) kJ · mol -1 and (-2571.68 ± 1.63) kJ · mol -1, respectively.