This standard specifies the method for determining the melting point of solid pesticide technical materials and reference standards, which can be used to assess the purity and consistency of pesticides through changes in melting point. The classical method described in the standard is the capillary tube method, where the sample is loaded into a capillary tube, placed in a U-shaped tube liquid bath (e.g., silicone oil) equipped with a stirring device, and heated at a controlled rate. The temperatures at which the sample begins to liquefy (meniscus point) and completely liquefies (liquefaction point) are observed. The instruments involved in the standard method mainly include a U-shaped tube, capillary tubes, a temperature-controlled heating device, a stirrer, an illumination device, and a calibrated thermometer. Nowadays, laboratories often use instruments that adhere to the principles of this standard but offer higher automation, such as fully automatic video melting point apparatuses, to improve observation accuracy and testing efficiency.