Low-temperature heat capacities Of L-3-(3,4-dihydroxyphenyl) alanine (C9H11NO4) were measured by a precision automated adiabatic calorimeter over the temperature range from (78 to 400) K. A polynomial equation of heat capacities as a function of temperature was fitted by the least-squares method. Based on the fitted polynomial, the smoothed heat capacities and thermodynamic functions of the compound relative to the standard reference temperature 298.15 K were calculated and tabulated at 5 K intervals. The constant-volume energy of combustion of the compound at T = 298.15 K was measured by a precision oxygen-bomb combustion calorimeter to be Delta U-c = -(21183.5 +/- 35.0) J.g(-1). The standard molar enthalpy of combustion of the compound was determined to be Delta H-c(m)o = -(4177.8 +/- 6.9) kJ.mol(-1), according to the definition of combustion enthalpy. Finally, the standard molar enthalpy of formation of the compound was calculated to be Delta H-f(m)o = -(935.9 +/- 7.0) kJ.mol(-1) in accordance with Hess law.