In Dexing Copper Mine, the ore from the mining district has an average gold grade of 0.196 g/t. As the gold grade is too low, using the existing analysis methods, there would be big deviations with regard to the analysis results. This would bring trouble to the guidance of gold production. To solve this problem, a determination method was studied that the gold contained in ore was pre-concentrated using foaming plastics,then organic agents were used to extract the gold from the destroyed gold-bearing foam plastics,and finally, gold was determined through direct spraying using the organic phase. This method greatly enhances the accuracy and sensitivity of gold determination.