In the present study, standard phytochemical method was conducted to identify quality some allelochemical compounds such as saponins, terpenoides, antraquinons, flavonoides, flavons by using 10 % condensed aquous extract in distilled water or ethanol solvent of root, stem and leaf organs of Atriplex lentiformis.Then the bioassay experiments were undertaken to evaluate the allelopathic potential of various concentrations (0, 20, 40, 60, 80 and 100%) of selected organs by using 10 % condensed aquous extract on radicle length, shoot length and germination percentage of Medicago scutellata to form of factorial examination in completely randomized design in the Hydroecology laboratory of Gonbad Kavous University in 2012. The effect of various concentrations of organs on studied parameters, was fitted to regression model. In the phytochemical examinations of the qualitative the allelochemicals of saponins and terpenoids were observed and confirmed while the allelochemicals like antraqouins, flavonoids and flavones were not detected in the studied organs. The bioassay of various concentrations from the selected organs and interaction effect of them showed the significant effect on different parameters of germinations of Medicago scutellata at p- value 0.05. The greatest hampering effect was found in the aquous leaf of Atriplex lentiformis as compared with other organs. The germination percentage of the M. scutellata compeletly was hampered by 80 and 100% of leaf organ. The effect of various concentrations on different parameters of germination indicated the highest R- square which was including linear and exponential dependent. The greatest R- square (R2=0.98) was found in aquous extract of root on the radicle length of the studied plant with linear dependent.