Abstract: Benzilic acid was found to be a specific masking agent for Ti at pH 58-5.5.When DCTAis used as the titrant, the so-called "DCTA-Benzilic acid masking method" should be used to titrate the Ti.The selectivity is very high, over 33 metal ions, such as Zr, Th, Bi, Fe, Al, La, Hg, Cu, Ni etc, will not interfere.This method can be used to determine the Ti in titanium ores, bauxites and silicates with rapidity and accuracy.