Abstract: Solid fat content (SFC) is an important quality indicator for describing fats and oils, such as cocoa butter and margarine. Low-field nuclear magnetic resonance (NMR) has become the mainstream method for measuring SFC due to its simplicity, speed, and lack of chemical reagents. The low-field NMR direct method is a relative measurement method that requires calibration and traceability of the instrument using a mixture of glycerol trioleate and glycerol tristearate. This paper introduces the principles of low-field NMR and SFC measurement, studies the traceability path of SFC for the glycerol trioleate/glycerol tristearate mixture, investigates its stability at different temperatures, analyzes the reasons for inaccurate measurement of mixed oil tubes at different temperature conditions, and finally determines the calibration method and temperature of the reference materials.