Native grasses from northeastern Mexico such as Aristida longiseta (Steud), Bouteloua gracilis (Thurb), Cenchrus incertus (M.A. Curtis), Hilaria berlangeri (Steud, Nash), Panicum hallii (Varsey) and Setaria macrostachya (H.B.K.) and introduced Cenchrus ciliaris (L), a cultivated grass, that are consumed by range small ruminants were evaluated to estimate seasonally, their neutral detergent fiber (NDF) content and the rate and extent of NDF digestion. Panicum hallii was lower (72, 34, 26%, respectively) in NDF, cellulose and hemicellulose content and A. longiseta was higher (87, 37, 37%). Cenchrus incertus (42%, annual mean) was higher in EDNDF and A. longiseta (25%) was lower. With exception of C. incertus, all native grasses had lower EDNDF than C. ciliaris (40%). Because of their low NDF digestion most native grasses could be considered poor food resources for range small ruminants.