Branched gold nanoparticles were grown on oxidized multiwalled carbon nanotubes by one-step reduction of gold chloride in water. The carbon nanotube/gold hybrids were used for the delivery of the anticancer drug doxorubicin hydrochloride into A549 lung cancer cell line. Doxorubicin (Dox) can be adsorbed in high quantity on both inner and outer surfaces of oxidized carbon nanotubes by pi-pi stacking interactions between doxorubicin aromatic groups and carbon nanotube (CNT) backbone. Carbon nanotube/gold hybrids display a broad, absorption band in the red and near infrared regions allowing their use for imaging applications. In vitro cellular tests showed that the nanostructures can efficiently transport and deliver doxorubicin inside the cells.