Abstract: With the development of national economy and the improvement of living standard，the demand for light coloured products is increasingly high.Therefore，the demand for the whiteness of inorganic powders is higher and higher.Taking light calcium carbonate as an example，in order to make its manufacturers understand the measures——how to enhance the product′s whiteness from theories to practice，this paper fully expatiated on various effecting factors of chemical whitening，process of chemical whitening，establishment principle of chemical whitening plan，laboratorial selection of optimal decision and methods of commercial test.In addition，several effective notes has also been put forward so as to guarantee the chemical whitening meet the expected results.