The properties of a mixed CdTe quantum dot/tetrahydro-4H-thiopyran-4-ylidene-functionalized polythiophene system are reported. This system was prepd. by exposing trioctylphosphine (TOP)-capped CdTe quantum dots to the polythiophene in soln. Strong fluorescence emission quenching and shortening of the fluopolythiophene and the quantum dots occur when they are mixed, indicating the occurrence of photoinduced charge sepn. Photoinduced absorption spectroscopy reveals a considerable decrease in the population of the polythiophene triplet excited state in the mixed system. These results demonstrate that between the quantum dots and the polythiophene there is both phys. and electronic contact, which is mediated by the tetrahydro-4H-thiopyran-4-ylidene side chains.