Taxonomic revision, relative abundance, reproductive biology, length-weight relation, conditionrnfactor and aspects of feeding of Lake Tana Garra species were studied from 2187 fish collectedrnduring January to December, 2006. Morphological, psychometric and mesmeric characters werernused to revise the taxonomy of the three already described species (G. tana, G. dembecha and G.rnregressus) and one different form of Garra (small mouth, sm). Cluster and principal componentrnanalyses using 23 external and 14 skull bone morphometric measurements revealed that G. tana andrnG. regressus are separate dissimilar species from others. G. dembecha and G. sm showed somernsimilarities, though the few meristic and morphological features were important to differentiaternthem. The % IRI (Index of Relative Importance) indicated that G. tana is abundant in the pelagicrnsites whereas G. sm is abundant in the littoral, and sub littoral sites having the rest of Garra speciesrnless abundant. Gonad-somatic index (GSI) and % frequency of ripe females were used torndetermine main breeding season. The main breeding time of G. regresses (April-October), G. tanarn(March-July) and G. December (May-July) was coincident with the rainy season of the area. G. smrnwas found to breed intensively during the dry season (November-March). G. tana is capable ofrnbreeding throughout the year, whereas G. December breeds only for three months. Extendedrnbreeding times were observed in G. sm and G. regresses. Significant differences were observedrnbetween the species for both sexes in the mean size at maturity, except for G. sm and G. December.rnAbsolute fecundity was found to be related rectilinear with standard length and linearly withrnbody and gonad weight for G.sm Regress and G. tana. The range of absolute fecundity wasrn(538.9-2968), (606-3397), (1215-1229) and (580.8-1800) for G. tana, G. sm, G. dembecha and G.rnregressus, respectively. The average relative fecundity was 63.3, 77.1, 102.7, and 55.5 for G.rndembecha, G. sm, G. tana and G. regressus, respectively. Both relative and absolute fecundity werernstatistically different (P< 0.001) between the species. Egg size frequency distribution revealed thatrnG. regresses was found to be multiple spawner, while G. December; G. tana and G. sm were singlernspanners. Except for G. December and G. regresses (Chi-square, P< 0.05), the sex ratio in the totalrncatch was not different from 1:1 for the other two species. The relationship between standard lengthrnand total weight was curvilinear for all the species, and isometric growth was assumed for all. Arnsignificant seasonal fluctuation (P< 0.0001) was observed in the condition of all Garra species. Thernbetter condition of these fishes during late dry and pre-rainy seasons was attributed to the increasernin temperature and availability of food. Microscopic examination of gut contents of G. sm, G. tana and G. December indicated that green, blue-green, diatoms and zooplanktons that are detrimental inrntheir origin were dominant.rnrnrnKey words and phrases: Condition factor, Food items, Garra, Lake Tana, Length-weight relation,Relative abundance, Reproductive biology, and Taxonomic revision.