The telomeres (molecular termini) of chromosomes play an important role in maintaining the structural integrity of the chromosome. Using a deoxyoligomer that contains the core sequence TTAGGG, we identified by fluorescence in situ hybridization (FISH) the telomeres on all 8 pairs of Schistosoma mansoni mitotic metaphase chromosomes. Our results indicate that S. mansoni exhibits a telomere sequence typical of other species.