Abstract: The current study evaluated the allelopathic potential of Alhagi graecorum on germination and seedling growth of two common crop plants; bean (Vicia faba) and corn (Zea mays). Water soluble allelochemicals were extracted from the air dried-powdered shoots of A. graecorum at three different concentrations (2.0, 4.0 and 6.0%, w/v). The germination experiment revealed that seeds of both bean and corn have tolerance to the aqueous extract of A. graecorum, where concentrations up to 6.0% had no significant effect on percent of germination as compared with the untreated seeds. The results showed that the lowest concentration (2.0%) of the aqueous extract stimulated elongation of radicle and plumule as well as seedling biomass of both bean and corn, while the highest concentration (6.0%) was inhibitory. In addition, the growth of corn seedlings was retarded at the modest dose (4%) of the aqueous extract, while that for bean seedlings was promoted at the same concentration. Similarly, water soluble allelochemicals extracted from A. gaecorum shoots influenced accumulation of soluble sugars and proteins in a concentration and species dependent manner.