A differential scanning calorimeter has a heat sink for accommodating therein a measurement sample and a reference material, and a differential heat flow detector that detects a temperature difference between the sample and the reference material. A cooling mechanism cools the heat sink, and a thermoconductor is disposed between the cooling mechanism and the heat sink and forms a heat flow path between the two. A first heater heats the heat sink, and a second heater heats the thermoconductor to thereby heat the heat sink. The second heater begins operating before the first heater nears its rated maximum output power.