Abstract: Different modifiers are used to modify the surface of calcium carbonate whiskers.The influences of modifier′s types，modification time as well as modifier′s dosages are investigated.Results show that when use a single modifier，sodium stearate′s effect is the best；when use sodium stearate and lauryl sodium sulfate（SDS） as a compound modifier，it turns out a better consequence.The effect of modification is noteworthy when adding the modifier before carbonization；and the optimum content of modified agents is 4%（mass fraction）.The optimal activation index can achieve 98% and sedimentation volume is 4.41 mL/g.Compared the IR spectra of modified with unmodified calcium carbonate whiskers，there occurs a methene，which show that modifiers are strongly bonded on calcium carbonate.

Key words: calcium carbonate whiskers, surface modification, activation index, sedimentation volume