The flotation foam viscosity is seriously affected and the production index is deteriorated by the mixing of underground filling materials in a gold mine in Shandong Province.Based on the characteristics of field production,and systematical sorting and analysis of various phenomena occurring in the flotation process without much adjustment to the existing production process,a series of experiments were carried out from the aspects of mixing proportion of slime and filling material,addition of new type filling material and elimination of the influence of filling material on flotation.The results show that the filling material will impose side effect on the flotation index and operation no matter what kind it is,and with its proportion over 1.0 %,the index is affected in a significant way;the addition of regulator such as ammonium sulfate,sodium silicate and ferrous sulfate can mitigate the influence of filling material to some extent while ammonium sulfate performs better:the recovery of gold is 96.1 % when ammonium sulfate is added at 1 000 g/t,meeting the production requirement.