The severe saline-alkali land was cultivated by special Fenglong machinery and by the conventional tractor rotary tillage (CK) 3 times within two years, soil bulk densities and salt contents in 0–20, 20–40 and 40–60 cm layers and the crop yields were measured and compared, and the effect and its mechanism of Fenlong tillage improving saline-alkali land were discussed. The results showed that Fenlong tillage reduced soil bulk density of 0–20 cm layer from the test before 1.27 g/cm3 to 1.06 g/cm³ with a decrease by 16.54%, while CK decreased soil bulk density of 0–20 cm layer from the test before 1.27 g/cm³ to 1.12 g/cm³ with a decrease by 11.81%, the former reduced 29.1% more than the latter. Immediate sampling after the first cultivation showed that the total salt contents in 0–20, 20–40 and 40–60 cm layers were 8.6, 5.7 and 4.4 g/kg for Fenlong tillage, 9.2, 4.9 and 4.2 g/kg for CK, and the variation ranges between the two tillage methods were –6.52%, 16.32% and 4.54%., respectively. For the third cultivation, summer maize was planted, and maize yield (fresh weight) was 12 150 kg/hm² for Fenlong tillage, 73.0% higher than CK (7 020 kg/hm²). At the end of this test, the total salt contents in 0–20, 20–40 and 40–60 cm were 4.3, 7.2 and 4.9 g/kg for Fenlong tillage, while 8.9, 4.7 and 4.3 g/kg for CK, and the variation ranges between the two tillage methods were –51.68%, 53.19% and 13.95%. The above results showed that Fenlong tillage could move the salt from the surface layer (0–20 cm) to the low layer while inhibit the salt in the low layer moving upwards, thus make the salt content in surface soil at a relatively low level, which is conducive to the normal germination and growth of crops.