Abstract: The adsorption of the Doxorubicin drug (DOX) which used as chemotherapy drug called an anthracycline to stop or slow the growth of cancer cell by Oxidized Carbon Nanotubes (O-CNTs) was studied. CNTs were synthesized by Flame Fragments Deposition (FFD) technique. Different concentrations of O-CNTs as a nanocarrier were added to 50 mL of DOX aqueous solution (10 ppm). Each mixture was stirred for ten minutes at 25°C at a pH = 4.8 for different periods of time. The O-CNTs/DOX mixture was isolated by centrifuging for 10 min at a rate of 6000 rpm. The concentrations of DOX in the supernatant liquid were recorded using a UV-Vis spectrophotometer by measuring the absorbance at 480 nm in order to find the ideal dose of CNTs for the drug’s optimum adsorption efficiency.