【Objective】This study aimed to explore the effects of applying different amounts of wood vinegar in combination with sheep manure on the improvement of saline-alkali soil in the low plain of Hebei and the salt tolerance of winter wheat from 2022 to 2024. 【Method】There were five treatments including conventional fertilization (CK), sheep manure at 27 t?hm-2 (T0), T0 + wood vinegar at 270 kg?hm-2 (T1), T0 + wood vinegar at 540 kg?hm-2 (T2), and T0 + wood vinegar at 810 kg?hm-2 (T3). The effects of the combined application of sheep manure with different amounts of wood vinegar on soil nutrients, salt tolerance characteristics of winter wheat, nutrient absorption and utilization, and yield were analyzed. 【Result】The results showed that at soil depth of 0-20 cm, the soil bulk density and electrical conductivity value under T2 treatments were significantly reduced by an average of 8.03% and 13.17% compared with CK (P < 0.05), while the total porosity, organic matter and available potassium contents significantly increased. The nitrate nitrogen content and available phosphorus under T2 were significantly increased compared with CK and T0. At a soil depth of 20-40 cm, the content of available phosphorus under T2 was significantly increased compared with CK. Compared with CK, T0, and T1, the content of soluble sugar and the activity of superoxide dismutase (SOD) at each filling stage, the soluble protein content and the activity of peroxidase at the early and middle filling stages, and the free amino acid content at the early filling stage in the flag leaf of T2 were significantly increased. Also, the content of superoxide anions radicals showed an opposite trend to the SOD activity while the total accumulation of nitrogen, phosphorus, and potassium under T2 in the aboveground part was significantly increased by 8.30% to 25.79% compared with CK, T0, and T1. The stomatal characteristic parameters of the flag leaf under T2 were significantly increased compared with CK, among which the stomatal size of the flag leaf under T2 was significantly increased by 21.23% compared with CK. Moreover, the yield of winter wheat under T2 treatment was significantly increased by 5.93% to 17.29% compared with CK, T0, and T1. Using mathematical modeling, it was observed that the optimal dosage of wood vinegar liquid following a simulation for a two-year period was close to the application amount of 540 kg?hm-2 of wood vinegar. 【Conclusion】Based on these results, it was recommended that the optimal amount of sheep manure to be applied should be 27 t?hm-2 while the amount of wood vinegar should be in the range of 535.46-551.03 kg?hm-2. This, could contribute to mitigating the negative impacts of saline-alkali soils and enhance winter wheat productivity in this region.