To explore the influence of the wheat seedling growth under nickel stress with exogenous betaine was studied the effects of rootapplying glycinebetaine (GB) with 1.0, 2.0, 3.0, 4.0, 5.0, 10.0, 15.0, 20.0 mmol·L^-1 treatments with 100 μmol·L^-1NiSO₄. And the physiological and biochemical indexes of stress resistance under the stress of 100 μmol·L^-1NiSO₄ by solution culture method. The results indicated that: (1) under the stress of 100 μmol·L^-1 of NiSO₄ , the root length,seedling height, fresh weight and dry weight decreased significantly by 14.7%, 11.7%, 15.0% and 16.7%, respecticely, as compared with the control. (2) With the increasing concentration of applied glycinebetaine, the root length, seedling height, fresh weight and dry weight increased at first and then descended, compared with the 100 μmol·L^-1 of NiSO₄. And the effect of exogenous GB with 4.0 mmol·L^-1 treatment was better. (3) Under the concentration of 4.0 mmol·L^-1 of GB, the activities of peroxidase (POD), superoxide dismutase (SOD), catalase (CAT) and ascorbate perxoidase (APX) in roots increased by 284.7%, 40.3%, 82.9% and 20.4%, respectively; Superoxide anion (O^-·₂) , hydrogen peroxide (H₂O₂) and malondialdehyde (MDA) contents decreased by 50.6%, 38.4% and 40.6%, respectively; soluble sugar and free proline contents decreased by 19.2%, 45.4%, respectively; Root activity significantly increased by 358.0%, compared with the 100 μmol·L^-1 of NiSO₄. Therefore, the appropriate concentration of rootapplying GB could significantly enhance the antioxidant capacity in root of wheat seedlings, and restore the root activity, so as to effectively reduce the harm of nickel stress on the growth of wheat seedlings.