Abstract: Through the hydroponic experiments, Triticum aestivum and Beckmannia syzigachne were treated with single stress by different concentrations of ZnSO₄ and CdSO₄ solutions. The physiological and biochemical characteristics of T.aestivum and B.syzigachne in germination and two-leaf one-heart period were analyzed, and the physiological changes under single stress of Zn and Cd were discussed. The results show that at the same processing level, under the stress of single Zn and single Cd, the contents of proline, soluble sugar, soluble protein, and MDA show an increasing trend in T.aestivum and B.syzigachne. With the increase of treatment concentration, the chlorophyll, soluble protein and peroxidase in T.aestivum and B.syzigachne increase firstly then reduce, but the contents of proline and MDA show a continuous upward trend. The contents of soluble sugar in T.aestivum and B.syzigachne increase firstly then reduced under the stress of Zn, while reduce firstly then increase under the stress of cadmium. Therefore, T.aestivum and B.syzigachne have certain tolerance to mild Zn and Cd single stress.