In this work, calcium lignosulphonate (CLS) was introduced as a novel flotation depressant for separation of scheelite from calcite. Sodium oleate (NaOl) acted as collector for scheelite. The flotation results showed that CLS had strong depressant effect on calcite flotation while exhibited little influence on scheelite flotation. Scheelite can be separated efficiently from scheelite-calcite mixed binary minerals in pH range of 7-11, when CLS was added prior to NaOl. The selective depressant effect of CLS on calcite was analyzed through interactions between the CLS micelles and mineral particles at water/particle interface.