[Objectives]To evaluate the impacts of the elemental sulfur (S0) and micro-algae (MA) co-fertilization on saline-alkaline soil of sunflower field in the Hetao Irrigation District (HID). [Methods]The greenhouse pot experiment was conducted with four treatments: control (CK), single S0fertilization (S), single MA fertilization (A), and S0and MA co-fertilization (SA) for comparing the selected soil properties and sunflower plant heights and weights in different treatments. [Results]The results showed that the mean soil organic matter (SOM) under the SA (25.08 g/kg) was significantly higher than that for the CK (20.59 g/kg), S (22.47 g/kg), and A (22.95 g/kg). The mean pH under the SA (7.75) was significantly lower than that for the CK (8.14), S (7.82), and A (7.96). The mean soil exchangeable Na+concentration under the SA was significantly lower than that for the S. The mean soil electrical conductivity (EC) under the SA was 9.76% lower than that for the S. The means of Cl-(1.22 g/kg) and width=31,height=15,dpi=110(1.90 g/kg) in soil under the SA were lower than that for the S (1.30, 2.06 g/kg)and A (1.31, 1.97 g/kg), respectively. For plant height 3 at the late stage of plant growth, the mean plant height 3 under the SA (89.00 cm) was higher than that of the CK (69.60 cm) and A (74.33 cm). The total weights of the fresh sunflower heads, fresh stems, and dry seeds under the SA were higher than that for the CK, S, and A. [Conclusions]In conclusion, the S0and MA co-fertilization had positive effects on improving saline-alkaline soils, the soil under the S0and MA co-fertilization could be better conditions for promoting sunflower growth than that for the S, Z, and CK, and thereby the S0and MA co-fertilization could be a new idea to improve saline-alkaline soil in the cold and arid regions.