d-Limonene has been studied by differential scanning calorimetry and adiabatic calorimetry. The heat capacities of a crystallized sample have been measured between 5 K and 250 K in an adiabatic calorimeter. The measured temperature and enthalpy of melting are (199.18 +/- 0.05) K and (11.38 +/- 0.02) kJ . mol(-1).