The genus Lilium has a huge nuclear genome size (approximately 13,400 to 46,900 Mbp), implying that Lilium genome is composed of a larger amount of repetitive sequences. To understand the organization of plant genome is required to observe repetitive DNA sequences found in the Lilium chromosome. In this study, Cot DNA analysis was introduced, in which repeated DNAs were assessed. The Cot analysis revealed that Cot-1 DNAs were a target region that contained highly and moderately repetitive sequences. In addition, Cot-1 DNA as a probe in fluorescence in situ hybridization (FISH) was used to detect somatic chromosomes at the metaphase stage of diploid (2x) Lilium tigrinum. The FISH analysis showed that bright fluorescent signals on the Cot-1 DNA were sporadically distributed in all over the L. tigrinum-chromosomes. However, relatively weak signals were displayed in nucleolarorganizing regions (NORs) of chromosome #1, #2, and #7 as follows: centromere and peri-centromere regions of all chromosomes; distinct DAPI band region in long arm of chromosome #8; and short arm of chromosome #7, #8, #9, #10, #11, and #12. In conclusion, the random Cot-1 DNA distribution pattern has proven that L. tigrinum genome is composed of dispersed repetitive DNAs.