Based on the working principles of meteorological platinum resistance temperature sensors, the form of the errors is proved by theoretical derivation, and the least square method is used to compensate the errors In addition, based on the experimental data, the compensation effect is verified, and the applicability and stability of the compensation scheme are discussedThe results show that the least square method of compensation can effectively reduce the error and improve the performance, so does the unqualified ones with the error in a certain range; but it is not applicable for the sensors with a high error of more than ±05 ℃ Although the starting compensation effect is obvious, but there is poor stability while working