Response of three stable dwarf mutant lines, namely dwf1, dwf2 and dwf3 to 170mM NaCl treatment was studied in comparison with untreated dwarf lines (positive control or PC) and treated mother varieties (used as negative control or NC) from 20d old seedling stage to maturity in grass pea (Lathyrus sativus L.). The three mutants differed significantly from both controls and also, from each other by onset of flowering, flower and pod production, their abortion, pollen fertility, different seed yield components, leaf injury level, plant dry weight and seed neurotoxin (β-ODAP) contents under salt stress. Among the five types of genotypes, dwf1 and dwf2 showed tolerance, while dwf3 was considered as a salt-sensitive line. Among the five genotypes, NC plants were the least tolerance to NaCl treatment.