Abstract: Suaeda aralocaspica is an annual halophyte species which is native to the Central Asian deserts. The dimorphic seeds of the studied species differ in seed color (black and brown). In order to discuss the response of the germination on dimorphic seeds of S. aralocaspica to salt stress,osmotic adjustment substances and the content of embryo Na⁺ and K⁺ under salt stress of dimorphic seeds were analyzed. For the brown seeds,the biomass,content of Na⁺ and K⁺ of the radicle and germ after germinated under different concentration of NaCl were tested. The osmotic adjustment substances and the degree of toxicity by saline ions of brown seeds were remarkable higher than that in black seeds. The Na⁺ content in radicle and germ of brown seeds were significantly increased with increasing of NaCl concentration,however,its increment in radicle is marked larger than germ. Salt stress had no effect on K⁺ content. The elongation speed and water content of radicle were significantly higher than germ in brown seeds,however the biomass of radicle and germ was on the contrary. In conclusion,dimorphic seeds of S. aralocaspica have different physiology and biochemistry response to salt stress. Responding to change in radicle and germ of brown seeds showed their super-strong adaptive capacity which will rapid germinate under high salinity stress.