This standard specifies the method for the determination of fluorine content in phosphate rocks and phosphate concentrates by ion-selective electrode method, which is suitable for the detection of fluorine content in the range of 0.5% to 5%. After muriatic acid analysis of the sample, using citric acid-sodium citrate buffer solution to control the ph value, and eliminating the interference of Miscellaneous ions, the fluorine content is determined by a potentiometer. This standard details the use and operation steps of reagents, instruments and equipment, providing a scientific basis for quality control and analysis in related fields.