PURPOSE: To obtain a thermal analyzer which makes a peak curve appear as a sharp one while the disturbance of the base line in a quantity-of-heat change curve obtained as the result of measurement is prevented.

CONSTITUTION: A differential thermal analyzer measures the temp. dependence of the properties of a sample 5 to be measured by the comparison of a reference substance 6 with the sample 5 to be measured and has soaking zones 19 respectively surrounding the sample 5 to be measured and the reference substance 6. The soaking zones 19 are provided one by one so as to individually surround the sample 5 to be measured and the reference substance 6.