The scope of the present study is to contribute to future breeding studies by determining the relationship between chromosome number and morphology of naturally occurring 18 genotypes of Turkish Lolium perenne. The chromosome number for all the studied genotypes was concurrently determined as 2n=14 (x=7). Their karyotypes showed a predominance of metacentric chromosomes. In the karyotype of one genotype, submetacentric chromosomes were dominant. A total of quantitative asymmetric indices were used to evaluate karyological features of the species. A meaningful dendrogram was carried out to assess the karyotype-symmetry conditions and described the karyotype relationships between different cytotypes. Chromosome lengths in a karyotype were between 1.52–2.95 µm and there was a broad variation in asymmetric index karyotype formula. It may be proposed that the populations of the Turkish perennial ryegrass have quite an important potential relevant to chromosomal variation, and therefore this variation gives essential opportunities to agronomists to develop new cultivars in the future.