Abstract: 【Objective】 To study the effects of different application combinations of Hexi Corridor saline-alkali soil improv on secondary saline-alkali soil improvement and sweet corn growth in Hexi Corridor, so as to determine the best application plan of improv. 【Methods】 Taking Tianyu 2 as the test crop, the effects of saline-alkali soil improv on seedling emergence rate, seedling preservation rate, plant height, stem diameter, plant fresh weight, yield composition, yield, economic benefit and soil saline-alkali index of sweet corn in the whole maize growth period were studied. 【Results】 The seedling emergence rate increased by 8.38%-11.00% when saline soil amendment was applied once with seeding water, and the seedling preservation rate increased by 13.31%-15.64% when saline soil amendment was applied twice with seeding water. The bald tip length of the third amendment was shortened by 44.30%, the rate of the first grade was up to 46.27%, and the yield and economic benefit were the best. Saline-alkali soil amendments applied in different periods can reduce soil saline-alkali indices, pH, EC and ESP by 0.15-0.35, 31-146 μs/cm and 0.8%-4.8%, respectively. 【Conclusion】 In summary, the best application time scheme of Hokang saline-alkali soil improver for soil improvement is: sowing time + improver 37.5 kg/hm², seedling stage + improver 30 kg/hm², spinning stage + improver 15 kg/hm².