Thanks to their cheap processability, organic optoelectronic devices are believed to gradually gain a non-negligible place on the market. However, their performances remain low, mainly because of the poor electron transport in conventional polymers used in such devices. Carbon nanotubes, with a bulk conductivity as high as 10E5 S/m, could therefore be seen as potential candidates to address this important issue. In this work, we have studied the use of a carbon nanotube and polymer composite as an active layer in organic light-emitting diodes and organic photovoltaic devices. Enhanced brightness was achieved using the composite as an electron-transport layer in organic light-emitting diodes, the best efficiency being obtained for those devices with a nanotube content of 1.2 %. Secondly, we have studied the use of the polymer and carbon nanotube composite as the active layer in organic photovoltaic cells. Photocurrents in such devices were greater than that of the cells without carbon nanotubes. It is believed that carbon nanotube composites could act as efficient transport media for charges, which were originally dissociated. This study has demonstrated that carbon nanotubes can be used as functional materials in organic optoelectronic devices and enhance the charge transport, hence the efficiency in such devices.