Abstract: Gold exhibits an extremely heterogeneous distribution in ore, and “nugget effect” often occurs, which results in poor precision and insufficient representativeness in analysis results and thus severely influences the accuracy of resource evaluation and development. By taking a highly heterogeneous gold ore in Inner Mongolia as the research object, the influence of key factors including the sample particle size, sampling quantity, calcination pre-treatment, and gold occurrence state on the stability of analysis results was systematically investigated. By adopting foam plastic adsorption-flame atomic absorption spectrometry （FAAS） as the core detection method, a comprehensive stability control procedure was proposed by combining detailed mineralogical identification and chemical phase analysis techniques. Results indicate that the studied gold ore is predominantly composed of exposed and semi-exposed native gold （>90%）, resulting in extremely high inherent sample variability. Particle size is the primary factor affecting analytical stability, and it is recommended to crush the sample to −0.074 mm without sieving to balance representativeness and avoid gold loss. Sampling quantity should be linked to gold grade. Specifically, for samples with gold grade no more than 5 g/t, the sampling quantity is 10 g, while for samples with gold grade more than 5 g/t, the sampling quantity is increased to 20−30 g, with 3−5 parallel determinations performed. Thorough sample homogenization （a combination of coning and quartering methods） is crucial for improving analytical precision, while the calcination step can be omitted for samples free of interfering components. The analytical stability control system for gold ore grade analysis, which takes particle size control as the foundation, sampling strategy as the core and thorough homogenization as the guarantee, provides a reliable method for the accurate analysis of gold ores with high variation coefficients and holds guiding significance for resource evaluation and rational development of similar deposits.