A process for preparing anilineboronic acid derivative of the formula I, by converting an aniline to a diprotected aniline by introducing two protecting groups, metalating the diprotected aniline with a metalating agent and simultaneously or subsequently reacting with a boronic ester B(OR1,2,3)3 to form a protected anilineboronic ester, which is converted, by detaching the protecting groups, to the anilineboronic esters of the formula (I).