A self-developed temperature-controlled consolidation test apparatus was used to conduct indoor tests on the thermal consolidation characteristics of a saturated powdery clay. The test apparatus includes a temperature control system, a peripheral pressure system, a counterpressure control system, and a pore water pressure measurement system, and the thermal consolidation tests were carried out at temperatures ranging from 25 °C to 50 °C, in which the sample peripheral pressures were 50 kPa, 100 kPa, and 150 kPa, respectively. The evolutions of the temperatures, the pore water pressures, and the strain of the consolidation body with the peripheral pressures in the course of the thermal consolidation process were analyzed by means of the test phenomena, the evolution of pore water pressure and solidus strain with peripheral pressure during the thermal consolidation process was analyzed through the experimental phenomena, and the evolution of pore water pressure and solidus strain with peripheral pressure was explained by applying the study of thermal property mechanism.