Chromosome numbers are reported here for six species of three genera of Cyprinidaernand one species of Cichlidae. Three of the species Labeobarbus nedgia, Labeobarbus.rnbrevicepalus and Labeobarbus intermedius are endemic to Ethiopia and Barbus humilis,rnBarbus pleurogramma, Garra dembecha and Oreochromis niloticus are native tornEthiopia. Chromosome preparation were made after colchicine injection in proportion tornbody size (0.5% of 0.8 ml/100 gm) and the fish were placed in aquarium for about 6-8rnhours to arrest mitotic chromosomes at metaphase stage. Then the specimens werernsacrificed and the gill filament were removed and kept in hypertonic solution (0.75 MrnKCl), after about 30 minutes the gills were fixed (3:1 methanol- acetic acid). Part ofrnthem were preserved for the other time and part of them were taken to grinding dish forrncrushing with glass rods by adding few drops of fixative. The cell suspensions that werernmade by grinding of the gill filament were filtered by gauze and centrifuged for 5rnminutes (1000 rpm) followed by splash slide preparation. Chromosomes were stainedrnwith Geimsa and mounted well. The following 2n chromosomes were observed for thernstudied seven species: Labeobarbus nedgia, 2n= 150, Labeobarbus brevicephalus,rn2n=150, Labeobarbus intermidus, 2n=150, B. humilis, 2n=50, B. pleurogramma, 2n=50,rnGarra dembeccha, 2n=50 and Oreochromis niloticus, 2n=44. The chromosome numbersrnwere determined from somatic mitotic chromosomes at metaphase stage. Polyploidy isrnevident in some of the species. Variable basic chromosome numbers were observed fromrnthe small and large Barbus fishes. Detailed studies of chromosome morphology were notrnpossible because of the smaller size and large number of the chromosomes. Note on therntaxonomy and distribution of each of the genera and species under study are provided. Itrnwas recommended that futher cytogenetical studies of the many species occurring in LakernTana, Ethiopia are required for better understanding of the phylogenetic and evolutionaryrnrelationships of the species.rnKey words: chromosome; Labeobarbus; Barbus; Garra; Oreochromis; Lake Tana;andrnphylogenetic