A temperature regulation plate 106 is divided into at least two areas, a heater 408 for applying a temperature load in correspondence with such areas and its control system are divided and controlled independently to set temperatures, and a cooling source is controlled by comparing the measurements from temperature sensors 409 arranged in respective areas for controlling the heater 408 and switching the measurement for calculating the control output sequentially thus reducing variation in in-plane temperature of a wafer due to heating when an electric load is applied. Since consumption and burning of a probe are prevented, highly reliable wafer level burn-in method and apparatus can be provided.