As an important equipment for semiconductor production, Rapid Thermal Annealing (RTA) needs precise and reliable temperature control. Usually, it uses a pyrometer to measure its temperature. In the use of the pyrometer, because of many reasons, the temperature of the pyrometer should be calibrated. On the basis of a certain imported rapid thermal annealing furnace, the temperature calibration method of its pyrometer is analyzed. Both thermocouple and melting-point sampling methods are presented and are used to enrich the sampling data for temperature calibration. The temperature calibration data in the range from 1000℃ to 1500℃ are estimated by linear calculation. Through the data sampling based on curve fitting, more accurate temperature calibration results are obtained. The advantages and disadvantages of both temperature calibration methods are analyzed by comparison. The result shows that the linear calculation temperature calibration method is more suitable for the temperature calibration below 1100℃ and the curve fitting temperature calibration method is more suitable for the temperature calibration above 1100℃.