A facile approach to prepare poly(3-hexylthiophene) (P3HT)/cadmium selenide quantum dot (CdSe QD) hybrid coaxial nanowires by a stepwise self-assembly process is reported. P3HT nanowires of approximate to 20 nm diameter are first prepared by self-assembly in a poor solvent such as cyclohexanone, and then as-prepared CdSe QDs are deposited compactly onto the P3HT nanowires by non-covalent interactions between P3HT and CdSe. When illuminated with white light, the hybrid nanowires show enhanced photoconductivity compared with the pristine P3HT nanowires and the blended nanocomposites.