Genome size has been estimated by flow cytometry in 14 populations belonging to eight taxa (seven species, one of them with two varieties) of the genus Tripleurospermum. 2C nuclear DNA amounts range from 4.87 to 9.22 pg, and nuclear DNA amounts per basic chromosome set from 1.99 to 2.75 pg. Statistically significant differences depending on ploidy level, life cycle or environmental factors such as altitude have been found. Also, genome size is positively correlated with total karyotype length. The presence of rhizome is related to nuclear DNA content in these species.