After the soil moisture sensor being installed, it is neccesary to make calibration on the soil conditions in the field for verifying the rating relation. In practice, field calibration of soil moisture sensor is a complicated step, during which high quality operation is needed, on-site taking soil is difficult, and it involves working long hours. In this study, the undisturbed soil columns were collected in field to send to laboratory, the soil was taken out after saturation, let a natural loss of soil moisture, then regularly weighting was made while the original values from the soil moisture sensor were recorded, so as to study the calibration of the soil moisture sensor, and discuss the ways of improving efficienty of installing soil moisture sensors.