Abstract-The moisture of green sand mainly refers to the water that can be got rid of at the temperature of 105℃-110℃, and it is affecting sand quality, one of the most important and sensitive parameters that affect the quality of green sand. At present, the methods for measuring the moisture content can be divided into two categories of direct and indirect methods. The precision of the direct method is high while the measurement period is long, so it does not suits to online measurement, and is often used to calibrate the indirect methods. In the indirect methods, the moisture content can be online obtained by measuring the physical parameters or performance indexes related to the moisture. They mainly include the resistance method, capacitance method, inductive method, microwave method, infrared spectrometry method, and nuclear magnetic resonance method.