Polysilsesquioxane films prepared by the copolymerization of dithienogermole dichloride (DTG-Cl) and bis(triethoxysilyl)-ethane (BTESE) exhibited sensing properties towards nitroaromatic compounds. These films also responded to aniline, a potential interfering matrix. However, selective sensing of nitrobenzene was possible and the film containing 2,6-dithienyldithienogermole as the sensing fluorophore underwent photoluminescence quenching only with nitrobenzene, but not with aniline.