One of the main aims of biosaline agriculture is the production of high quality forages by halophyte plants. Kochia is a halophyte plant which has a proper capability for forage production. Evaluation of nutritive value and anti-nutritional compounds of Kochia ecotypes under saline irrigation was the goal of this experiment. Three saline irrigation waters (5.2, 10.5 and 23.1 dS m^-1) and three Iranian kochia ecotypes (Birjand, Borujerd and Sabzevar) were assigned as the main and sub plots, respectively, in a split plot design based on RCBD with three replications. The results showed that in vitro dry matter digestibility of leaf and whole aboveground organs were not affected by salinity, while in vitro stem dry matter digestibility increased under the severe salinity conditions. Organic matter digestibility of leaf, stem and whole plant at 10.5 dS m^-1 were higher than other salinity levels. Crude proteins in whole plant increased by salinity but there were no significant difference among ecotypes. Increasing salinity levels decreased the percentage of neutral detergent fiber (NDF) and acid detergent fibre (ADF) in whole plant. Percentage of whole plant NDF in Sabzevar ecotype was more than other populations, but there were no significant differences among populations in whole plant ADF. The total phenol and tannin content showed an increasing trend with increased salinity levels, though it was not significant among salinity levels. Total phenol and tannin accumulation in Sabzevar population was more than other populations. Generally, kochia forage quality is comparable with other common forage crops at the beginning of anthesis stage and there were no differences between the forage quality of studied populations up to the salinity level of 23.1 dS m^-1.