An altered rock type low-sulfide gold-bearing ore with a primary slime content of up to 15 % is processed in a flotation plant,which is not a smooth production flowsheet and ineffective.Through 2 technical renovation,the coarse crushing+semi-auto grinding+ball mill grinding process and the preferential flotation with flotation column+roughing,cleaning and scavenging with column-cell joint flotation process are decided and have achieved good results:the production scale has increased from 600 t/d to 1 500 t/d,the gold recovery rate has increased by 1.48 percentage points,the annual profits created can be 14.896 million yuan.The process can generate great economic and social benefits.