The　use　of　ammonium　dibutyl　dithiophosphate　(ADD)　as　a　collector　in　the　flotation　of　slime　-containing　copper　sulfide　ore　typically　produces　a　sticky　froth,　which　results　in　poor　flotation.　The　mechanism　and　effects　of　copper　sulfide　ore　flotation　in　synergistic　systems　comprising　ADD　and　terpenic　oil　reagents　have　been　systematically　investigated　to　solve　this　problem.　A　high　ratio　of　ADD　to　terpenic　oil　is　not　conducive　to　the　flotation　of　fine-grained　copper　sulfide　ores;　however,　adjusting　this　ratio　may　improve　floatation　by　reducing　the　effect　of　the　slime.　Lowering　the　ratio　from　5:1　to　1:1　increased　the　copper　grade　from　17.7%　to　20.8%,　while　the　recovery　was　largely　unchanged.　Notably,　adjusting　this　ratio　also　reduced　the　cost　of　the　flotation　reagent.　To　study　the　mechanism　by　which　the　ADD-to-terpenic　oil　ratio　affects　the　foam　performance,　the　froth　stability　tests　of　the　gas-liquid　two-phase　and　gas-liquid-solid　three-phase　systems　were　performed.　Reducing　the　proportion　of　ADD　reduced　the　froth　water　content　and　weakened　the　ability　of　the　froth　to　collect　gangue　by　adsorbtion　with　copper　ions;　this　reduced　gangue　entrainment　and　maximized　recovery　and　product　quality.