The first self-immolative dendritic glucuronide prodrug of doxorubicin was studied with the aim to target β-glucuronidase overexpressed in the microenvironment of numerous tumors. This compound includes a chemical amplifier programmed to release two molecules of doxorubicin after a single enzymatic activation step. Upon β-glucuronidase activation, the dendritic prodrug was twice more toxic than its monomeric counterpart against H661 lung cancer cells.