Chromosome data have contributed little towards resolving the problems ofrnclassification and phylogeny orthe Swertia species (Y uan, 1993). For many species ofrnthe genus the chromosome number as weJ[ as morphology were not stud ied (Yuan andrnKUpfer, 1993).rnIn the present work, ch romosome numbers were documented for six species of SwerliarnL. (Gentianaceae) from Ethiopia. S. fimbria/a, s. kiJill/wu/s charica, S. macrosepa/arnsubsp. microsperma and S. va/kensii var. baleellsis were found to be diploid withrn2n=26. S. crassillscula subsp. robllsta was dip loid with 211=20. The above chromosomernnumbers were determined from mitotic chromosomes. Diploid (211=20, n"" I 0) andrntetraploid (2n=40, n=20) chromosome numbers were found for S. abyssillica fromrnmeiot ic chromosome study. The chromosome numbers of S. crassilisclila subsp.rnrobusta , S macrosepala subsp. microsperma, S volkellsii val'. baleensis and 211=40rncytotype of S. abyssil/ica were reported for the first time. Further, the present studyrnconfimled previous reports on the chromosome numbers of the remaining species andrnthe basic chromosome number x= 13 and x=1 0 for the genus.rnKaryotypes of five species of SlI'ertia namely, S fimbria/a , S. kilimalltischarica, S.rnmacrosepala subsp. microsperma. S. crassiuscula subsp. robusta and S. volkensii val'.rnbaleellsis have been described and their similarities and differences were discussed.rnEven though tile chromosome morphology of these species is very similar, somernvariat ions in basic number, ploidy level, satell ite number and size of chromosomesrnwere observed among the Swerlia species studied. The study revealed that the spec iesrnwere heterogeneous. It is recommended that fu rther study of karyotype of all thernspecies of the genus including chromosome banding is necessary to complete therncytotaxonomic knowledge of the genus as a whole.