A mesoporous silica has uniform mesopores and a periodic structure, which contains
a Zr element in the form of a Si—O—Zr bond and wherein the Zr content
in the Si—O—Zr bond, represented by [Zr/(Si+Zr)] is 0.05 to 20 mole
%. The mesoporous silica is superior in alkali resistance and is suitably used
particularly as a separation membrane (e.g. a ceramic membrane) and a catalytic
support for solid-liquid system, in which an alkaline liquid may be used.