Abstract: Lipid biostimulants are a class of microbially produced metabolites with amphiphilic structures, exhibiting significant application potential in enhancing plant physiological resistance and soil remediation. However, their role and mechanisms in promoting desert plant growth and improving wind-blown sandy soils remain unclear. This study employed a two-factor design in the Mu Us Desert experimental area, establishing four lipid biostimulant concentration gradients (S0: undiluted; S1: 100-fold dilution; S2, 300-fold dilution; S3, 600-fold dilution) and three fertilizer treatments (F0, no additional fertilizer; F1, microbial inoculant; F2, organic water-soluble fertilizer). The effects of these treatments on alfalfa growth and the physicochemical properties of wind-blown sandy soil were investigated. The optimal application scheme was selected through a multi-objective comprehensive evaluation using the Entropy Weight-TOPSIS model. Results indicated: (1) Compared to the control, the S1F1 treatment significantly enhanced alfalfa growth and soil improvement. Alfalfa plant height, yield, and crude protein content increased by 49.10%, 75.97%, and 19.68%, respectively. Concurrently, it markedly reduced malondialdehyde and proline levels in plants, enhanced stress resistance, and decreased cellular oxidative damage; (2) Under S1F1 treatment, organic matter content in wind-blown sandy soil increased by 27.10%, available phosphorus content rose by 151.75%, and urease activity improved by 166.05%, with significant enhancements in soil fertility and microbial activity; (3) Lipid-based biostimulants diluted 100-fold achieved higher comprehensive evaluation scores across all concentration treatments. The S1F1 treatment scored the highest at 0.6794, representing the optimal combination for high-yield, high-quality alfalfa production and soil improvement in wind-sand areas. Experiments demonstrate that seed treatment with 100-fold diluted lipid biostimulant combined with microbial fertilizer application constitutes an effective technical solution for enhancing forage yield and improving soil fertility in the Mu Us region. This research provides theoretical foundations and technical support for boosting forage production and soil improvement in wind-sand areas.