Since the vast territory of China, the temperature difference between North and South is very large especially in the chill winter. The North sites temperature is under -40℃.In order to master the effect of humidity accuracy caused by the environment temperature changing, random select would be done as below: the 3 humidity sensors of type 155 as the standards was selected to do the comparison on the different temperature points by using the two-pressure humidity generator. The measurement accuracy comparison of the 3 Humidity sensors and chill drew-point is used to prove the relative and difference between the two calculating methods on the humidity measurement and then to analysis the temperature correction of humidity measurement at 0～-40℃.